diff --git a/README.md b/README.md
index 2da839bc..feef033c 100644
--- a/README.md
+++ b/README.md
@@ -21,7 +21,7 @@ Test-driven from Swift and implemented in Objective-C, to avoid burdening Object
 - [x] PKCS12 client certificates using the [TLS auth mechanism plugin](https://github.com/rabbitmq/rabbitmq-auth-mechanism-ssl)
 - [ ] [PKCS12 client certificates using chained CAs](https://github.com/rabbitmq/rabbitmq-objc-client/issues/74)
 - [ ] [Publisher confirmations](https://github.com/rabbitmq/rabbitmq-objc-client/issues/68)
-- [ ] [Publish and consume messages as data](https://github.com/rabbitmq/rabbitmq-objc-client/issues/46)
+- [x] [Publish and consume messages as data](https://github.com/rabbitmq/rabbitmq-objc-client/issues/46)
 - [ ] [Connection closure when broker doesn't send heartbeats fast enough](https://github.com/rabbitmq/rabbitmq-objc-client/issues/41)
 - [ ] [Customisable consumer hooks](https://github.com/rabbitmq/rabbitmq-objc-client/issues/71)
 - [ ] [basic.return support](https://github.com/rabbitmq/rabbitmq-objc-client/issues/72)
@@ -90,9 +90,9 @@ this list.
    ```swift
    let q = ch.queue("myqueue")
    q.subscribe { m in
-      print("Received: \(m.content)")
+      print("Received: \(m.body)")
    }
-   q.publish("foo")
+   q.publish("foo".dataUsingEncoding(NSUTF8StringEncoding)!)
    ```
 
 1. Close the connection when done:
diff --git a/RMQClient/RMQAllocatedChannel.m b/RMQClient/RMQAllocatedChannel.m
index d10510d5..bee9277b 100644
--- a/RMQClient/RMQAllocatedChannel.m
+++ b/RMQClient/RMQAllocatedChannel.m
@@ -242,7 +242,7 @@ - (void)basicCancel:(NSString *)consumerTag {
                                                                         options:RMQBasicCancelNoOptions]];
 }
 
-- (void)basicPublish:(NSString *)message
+- (void)basicPublish:(NSData *)body
           routingKey:(NSString *)routingKey
             exchange:(NSString *)exchange
           properties:(NSArray<RMQValue *> *)properties
@@ -251,8 +251,7 @@ - (void)basicPublish:(NSString *)message
                                                                  exchange:[[RMQShortstr alloc] init:exchange]
                                                                routingKey:[[RMQShortstr alloc] init:routingKey]
                                                                   options:options];
-    NSData *contentBodyData = [message dataUsingEncoding:NSUTF8StringEncoding];
-    RMQContentBody *contentBody = [[RMQContentBody alloc] initWithData:contentBodyData];
+    RMQContentBody *contentBody = [[RMQContentBody alloc] initWithData:body];
 
     NSData *bodyData = contentBody.amqEncoded;
 
@@ -282,15 +281,13 @@ -  (void)basicGet:(NSString *)queue
                                                                    options:options]
                   completionHandler:^(RMQFrameset *frameset) {
                       RMQBasicGetOk *getOk = (RMQBasicGetOk *)frameset.method;
-                      NSString *messageContent = [[NSString alloc] initWithData:frameset.contentData
-                                                                       encoding:NSUTF8StringEncoding];
-                      RMQMessage *message = [[RMQMessage alloc] initWithContent:messageContent
-                                                                    consumerTag:@""
-                                                                    deliveryTag:@(getOk.deliveryTag.integerValue)
-                                                                    redelivered:getOk.options & RMQBasicGetOkRedelivered
-                                                                   exchangeName:getOk.exchange.stringValue
-                                                                     routingKey:getOk.routingKey.stringValue
-                                                                     properties:frameset.contentHeader.properties];
+                      RMQMessage *message = [[RMQMessage alloc] initWithBody:frameset.contentData
+                                                                 consumerTag:@""
+                                                                 deliveryTag:@(getOk.deliveryTag.integerValue)
+                                                                 redelivered:getOk.options & RMQBasicGetOkRedelivered
+                                                                exchangeName:getOk.exchange.stringValue
+                                                                  routingKey:getOk.routingKey.stringValue
+                                                                  properties:frameset.contentHeader.properties];
                       userCompletionHandler(message);
                   }];
 }
@@ -439,16 +436,15 @@ - (void)handleConfirmation:(RMQFrameset *)frameset {
 
 - (void)handleBasicDeliver:(RMQFrameset *)frameset {
     RMQBasicDeliver *deliver = (RMQBasicDeliver *)frameset.method;
-    NSString *content = [[NSString alloc] initWithData:frameset.contentData encoding:NSUTF8StringEncoding];
     RMQConsumer *consumer = self.consumers[deliver.consumerTag.stringValue];
     if (consumer) {
-        RMQMessage *message = [[RMQMessage alloc] initWithContent:content
-                                                      consumerTag:deliver.consumerTag.stringValue
-                                                      deliveryTag:@(deliver.deliveryTag.integerValue)
-                                                      redelivered:deliver.options & RMQBasicDeliverRedelivered
-                                                     exchangeName:deliver.exchange.stringValue
-                                                       routingKey:deliver.routingKey.stringValue
-                                                       properties:frameset.contentHeader.properties];
+        RMQMessage *message = [[RMQMessage alloc] initWithBody:frameset.contentData
+                                                   consumerTag:deliver.consumerTag.stringValue
+                                                   deliveryTag:@(deliver.deliveryTag.integerValue)
+                                                   redelivered:deliver.options & RMQBasicDeliverRedelivered
+                                                  exchangeName:deliver.exchange.stringValue
+                                                    routingKey:deliver.routingKey.stringValue
+                                                    properties:frameset.contentHeader.properties];
         consumer.handler(message);
     }
 }
diff --git a/RMQClient/RMQChannel.h b/RMQClient/RMQChannel.h
index 3883125e..433ba9ab 100644
--- a/RMQClient/RMQChannel.h
+++ b/RMQClient/RMQChannel.h
@@ -97,7 +97,7 @@
 
 - (void)basicCancel:(nonnull NSString *)consumerTag;
 
-- (void)basicPublish:(nonnull NSString *)message
+- (void)basicPublish:(nonnull NSData *)body
           routingKey:(nonnull NSString *)routingKey
             exchange:(nonnull NSString *)exchange
           properties:(nonnull NSArray<RMQValue *> *)properties
diff --git a/RMQClient/RMQExchange.h b/RMQClient/RMQExchange.h
index fbf720a8..ce86e657 100644
--- a/RMQClient/RMQExchange.h
+++ b/RMQClient/RMQExchange.h
@@ -72,19 +72,19 @@
 - (void)unbind:(RMQExchange *)source;
 - (void)delete:(RMQExchangeDeleteOptions)options;
 - (void)delete;
-- (void)publish:(NSString *)message
+- (void)publish:(NSData *)body
      routingKey:(NSString *)routingKey
      properties:(NSArray <RMQValue<RMQBasicValue> *> *)properties
         options:(RMQBasicPublishOptions)options;
-- (void)publish:(NSString *)message
+- (void)publish:(NSData *)body
      routingKey:(NSString *)key
      persistent:(BOOL)isPersistent
         options:(RMQBasicPublishOptions)options;
-- (void)publish:(NSString *)message
+- (void)publish:(NSData *)body
      routingKey:(NSString *)key
      persistent:(BOOL)isPersistent;
-- (void)publish:(NSString *)message
+- (void)publish:(NSData *)body
      routingKey:(NSString *)key;
-- (void)publish:(NSString *)message;
+- (void)publish:(NSData *)body;
 
 @end
diff --git a/RMQClient/RMQExchange.m b/RMQClient/RMQExchange.m
index 15f164dc..f4a8cfc8 100644
--- a/RMQClient/RMQExchange.m
+++ b/RMQClient/RMQExchange.m
@@ -106,18 +106,18 @@ - (void)delete {
     [self delete:RMQExchangeDeleteNoOptions];
 }
 
-- (void)publish:(NSString *)message
+- (void)publish:(NSData *)body
      routingKey:(NSString *)routingKey
      properties:(NSArray<RMQValue<RMQBasicValue> *> *)properties
         options:(RMQBasicPublishOptions)options {
-    [self.channel basicPublish:message
+    [self.channel basicPublish:body
                     routingKey:routingKey
                       exchange:self.name
                     properties:properties
                        options:options];
 }
 
-- (void)publish:(NSString *)message
+- (void)publish:(NSData *)body
      routingKey:(NSString *)key
      persistent:(BOOL)isPersistent
         options:(RMQBasicPublishOptions)options {
@@ -125,31 +125,31 @@ - (void)publish:(NSString *)message
     if (isPersistent) {
         [properties addObject:[[RMQBasicDeliveryMode alloc] init:2]];
     }
-    [self.channel basicPublish:message
+    [self.channel basicPublish:body
                     routingKey:key
                       exchange:self.name
                     properties:properties
                        options:options];
 }
 
-- (void)publish:(NSString *)message
+- (void)publish:(NSData *)body
      routingKey:(NSString *)key
      persistent:(BOOL)isPersistent {
-    [self publish:message
+    [self publish:body
        routingKey:key
        persistent:isPersistent
           options:RMQBasicPublishNoOptions];
 }
 
-- (void)publish:(NSString *)message
+- (void)publish:(NSData *)body
      routingKey:(NSString *)key {
-    [self publish:message
+    [self publish:body
        routingKey:key
        persistent:NO];
 }
 
-- (void)publish:(NSString *)message {
-    [self publish:message
+- (void)publish:(NSData *)body {
+    [self publish:body
        routingKey:@""];
 }
 
diff --git a/RMQClient/RMQMessage.h b/RMQClient/RMQMessage.h
index 76583b99..cb2b0b93 100644
--- a/RMQClient/RMQMessage.h
+++ b/RMQClient/RMQMessage.h
@@ -53,7 +53,7 @@
 #import "RMQBasicProperties.h"
 
 @interface RMQMessage : RMQValue
-@property (nonatomic, readonly) NSString *content;
+@property (nonatomic, readonly) NSData *body;
 @property (nonatomic, readonly) NSString *consumerTag;
 @property (nonatomic, readonly) NSNumber *deliveryTag;
 @property (nonatomic, readonly) BOOL isRedelivered;
@@ -61,13 +61,13 @@
 @property (nonatomic, readonly) NSString *routingKey;
 @property (nonatomic, readonly) NSArray *properties;
 
-- (instancetype)initWithContent:(NSString *)content
-                    consumerTag:(NSString *)consumerTag
-                    deliveryTag:(NSNumber *)deliveryTag
-                    redelivered:(BOOL)isRedelivered
-                   exchangeName:(NSString *)exchangeName
-                     routingKey:(NSString *)routingKey
-                     properties:(NSArray<RMQValue<RMQBasicValue> *> *)properties;
+- (instancetype)initWithBody:(NSData *)body
+                 consumerTag:(NSString *)consumerTag
+                 deliveryTag:(NSNumber *)deliveryTag
+                 redelivered:(BOOL)isRedelivered
+                exchangeName:(NSString *)exchangeName
+                  routingKey:(NSString *)routingKey
+                  properties:(NSArray<RMQValue<RMQBasicValue> *> *)properties;
 
 - (NSString *)appID;
 - (NSString *)contentType;
diff --git a/RMQClient/RMQMessage.m b/RMQClient/RMQMessage.m
index 05e1cc8a..1fee1561 100644
--- a/RMQClient/RMQMessage.m
+++ b/RMQClient/RMQMessage.m
@@ -52,7 +52,7 @@
 #import "RMQMessage.h"
 
 @interface RMQMessage ()
-@property (nonatomic, readwrite) NSString *content;
+@property (nonatomic, readwrite) NSData *body;
 @property (nonatomic, readwrite) NSString *consumerTag;
 @property (nonatomic, readwrite) NSNumber *deliveryTag;
 @property (nonatomic, readwrite) BOOL isRedelivered;
@@ -63,16 +63,16 @@ @interface RMQMessage ()
 
 @implementation RMQMessage
 
-- (instancetype)initWithContent:(NSString *)content
-                    consumerTag:(NSString *)consumerTag
-                    deliveryTag:(NSNumber *)deliveryTag
-                    redelivered:(BOOL)isRedelivered
-                   exchangeName:(NSString *)exchangeName
-                     routingKey:(NSString *)routingKey
-                     properties:(NSArray<RMQValue<RMQBasicValue> *> *)properties {
+- (instancetype)initWithBody:(NSData *)body
+                 consumerTag:(NSString *)consumerTag
+                 deliveryTag:(NSNumber *)deliveryTag
+                 redelivered:(BOOL)isRedelivered
+                exchangeName:(NSString *)exchangeName
+                  routingKey:(NSString *)routingKey
+                  properties:(NSArray<RMQValue<RMQBasicValue> *> *)properties {
     self = [super init];
     if (self) {
-        self.content = content;
+        self.body = body;
         self.consumerTag = consumerTag;
         self.deliveryTag = deliveryTag;
         self.isRedelivered = isRedelivered;
diff --git a/RMQClient/RMQQueue.h b/RMQClient/RMQQueue.h
index 55b7bc57..d6b17c51 100644
--- a/RMQClient/RMQQueue.h
+++ b/RMQClient/RMQQueue.h
@@ -75,15 +75,15 @@
 - (void)unbind:(RMQExchange *)exchange;
 - (void)delete:(RMQQueueDeleteOptions)options;
 - (void)delete;
-- (void)publish:(NSString *)message
+- (void)publish:(NSData *)body
      properties:(NSArray <RMQValue<RMQBasicValue> *> *)properties
         options:(RMQBasicPublishOptions)options;
-- (void)publish:(NSString *)message
+- (void)publish:(NSData *)body
      persistent:(BOOL)isPersistent
         options:(RMQBasicPublishOptions)options;
-- (void)publish:(NSString *)message
+- (void)publish:(NSData *)body
      persistent:(BOOL)isPersistent;
-- (void)publish:(NSString *)message;
+- (void)publish:(NSData *)body;
 - (void)pop:(RMQConsumerDeliveryHandler)handler;
 - (RMQConsumer *)subscribe:(RMQConsumerDeliveryHandler)handler;
 - (RMQConsumer *)subscribe:(RMQBasicConsumeOptions)options
diff --git a/RMQClient/RMQQueue.m b/RMQClient/RMQQueue.m
index 7dc6ab87..a560d37f 100644
--- a/RMQClient/RMQQueue.m
+++ b/RMQClient/RMQQueue.m
@@ -104,37 +104,37 @@ - (void)delete {
     [self delete:RMQQueueDeleteNoOptions];
 }
 
-- (void)publish:(NSString *)message
+- (void)publish:(NSData *)data
      properties:(NSArray<RMQValue<RMQBasicValue> *> *)properties
         options:(RMQBasicPublishOptions)options {
-    [self.channel basicPublish:message
+    [self.channel basicPublish:data
                     routingKey:self.name
                       exchange:@""
                     properties:properties
                        options:options];
 }
 
-- (void)publish:(NSString *)message
+- (void)publish:(NSData *)body
      persistent:(BOOL)isPersistent
         options:(RMQBasicPublishOptions)options {
     NSMutableArray *properties = [NSMutableArray new];
     if (isPersistent) {
         [properties addObject:[[RMQBasicDeliveryMode alloc] init:2]];
     }
-    [self.channel basicPublish:message
+    [self.channel basicPublish:body
                     routingKey:self.name
                       exchange:@""
                     properties:properties
                        options:options];
 }
 
-- (void)publish:(NSString *)message
+- (void)publish:(NSData *)body
      persistent:(BOOL)isPersistent {
-    [self publish:message persistent:isPersistent options:RMQBasicPublishNoOptions];
+    [self publish:body persistent:isPersistent options:RMQBasicPublishNoOptions];
 }
 
-- (void)publish:(NSString *)message {
-    [self publish:message persistent:NO];
+- (void)publish:(NSData *)body {
+    [self publish:body persistent:NO];
 }
 
 - (void)pop:(RMQConsumerDeliveryHandler)handler {
diff --git a/RMQClientIntegrationTests/ConnectionRecoveryIntegrationTest.swift b/RMQClientIntegrationTests/ConnectionRecoveryIntegrationTest.swift
index adbda23f..d38a3768 100644
--- a/RMQClientIntegrationTests/ConnectionRecoveryIntegrationTest.swift
+++ b/RMQClientIntegrationTests/ConnectionRecoveryIntegrationTest.swift
@@ -26,7 +26,7 @@
 // Version 1.1 (the "License"); you may not use this file except in
 // compliance with the License. You may obtain a copy of the License at
 // https://www.mozilla.org/MPL/
-//
+// 
 // Software distributed under the License is distributed on an "AS IS"
 // basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
 // License for the specific language governing rights and limitations
@@ -89,7 +89,7 @@ class ConnectionRecoveryIntegrationTest: XCTestCase {
 
         ch.confirmSelect()
 
-        ex1.publish("before close")
+        ex1.publish("before close".dataUsingEncoding(NSUTF8StringEncoding))
         XCTAssertEqual(0, dispatch_semaphore_wait(consumerSemaphore, TestHelper.dispatchTimeFromNow(semaphoreTimeout)),
                        "Timed out waiting for message")
 
@@ -98,9 +98,9 @@ class ConnectionRecoveryIntegrationTest: XCTestCase {
         XCTAssert(TestHelper.pollUntil { delegate.recoveredConnection != nil },
                   "Didn't finish recovery")
 
-        q.publish("after close 1")
+        q.publish("after close 1".dataUsingEncoding(NSUTF8StringEncoding))
         dispatch_semaphore_wait(consumerSemaphore, TestHelper.dispatchTimeFromNow(semaphoreTimeout))
-        ex1.publish("after close 2")
+        ex1.publish("after close 2".dataUsingEncoding(NSUTF8StringEncoding))
         dispatch_semaphore_wait(consumerSemaphore, TestHelper.dispatchTimeFromNow(semaphoreTimeout))
 
         var acks: Set<NSNumber>?
@@ -111,7 +111,9 @@ class ConnectionRecoveryIntegrationTest: XCTestCase {
             dispatch_semaphore_signal(confirmSemaphore)
         }
 
-        XCTAssertEqual(["before close", "after close 1", "after close 2"], messages.map { $0.content })
+        XCTAssertEqual("before close".dataUsingEncoding(NSUTF8StringEncoding), messages[0].body)
+        XCTAssertEqual("after close 1".dataUsingEncoding(NSUTF8StringEncoding), messages[1].body)
+        XCTAssertEqual("after close 2".dataUsingEncoding(NSUTF8StringEncoding), messages[2].body)
 
         XCTAssertEqual(0, dispatch_semaphore_wait(confirmSemaphore, TestHelper.dispatchTimeFromNow(semaphoreTimeout)))
         XCTAssert(acks!.union(nacks!).isSupersetOf([2, 3]),
@@ -119,10 +121,10 @@ class ConnectionRecoveryIntegrationTest: XCTestCase {
 
         // test recovery of queue arguments - in this case, x-max-length
         consumer.cancel()
-        q.publish("4")
-        q.publish("5")
-        q.publish("6")
-        q.publish("7")
+        q.publish("4".dataUsingEncoding(NSUTF8StringEncoding))
+        q.publish("5".dataUsingEncoding(NSUTF8StringEncoding))
+        q.publish("6".dataUsingEncoding(NSUTF8StringEncoding))
+        q.publish("7".dataUsingEncoding(NSUTF8StringEncoding))
 
         var messagesPostCancel: [RMQMessage] = []
         q.subscribe { m in
@@ -133,7 +135,9 @@ class ConnectionRecoveryIntegrationTest: XCTestCase {
         for _ in 5...7 {
             XCTAssertEqual(0, dispatch_semaphore_wait(consumerSemaphore, TestHelper.dispatchTimeFromNow(semaphoreTimeout)))
         }
-        XCTAssertEqual(["5", "6", "7"], messagesPostCancel.map { $0.content })
+        XCTAssertEqual("5".dataUsingEncoding(NSUTF8StringEncoding), messagesPostCancel[0].body)
+        XCTAssertEqual("6".dataUsingEncoding(NSUTF8StringEncoding), messagesPostCancel[1].body)
+        XCTAssertEqual("7".dataUsingEncoding(NSUTF8StringEncoding), messagesPostCancel[2].body)
     }
 
     func testReenablesConsumersOnEachRecoveryFromConnectionClose() {
@@ -167,7 +171,7 @@ class ConnectionRecoveryIntegrationTest: XCTestCase {
             dispatch_semaphore_signal(semaphore)
         }
 
-        ex.publish("before close")
+        ex.publish("before close".dataUsingEncoding(NSUTF8StringEncoding))
         XCTAssertEqual(0, dispatch_semaphore_wait(semaphore, TestHelper.dispatchTimeFromNow(semaphoreTimeout)),
                        "Timed out waiting for message")
 
@@ -177,24 +181,30 @@ class ConnectionRecoveryIntegrationTest: XCTestCase {
                   "Didn't finish recovery the first time")
         delegate.recoveredConnection = nil
 
-        q.publish("after close 1")
+        q.publish("after close 1".dataUsingEncoding(NSUTF8StringEncoding))
         dispatch_semaphore_wait(semaphore, TestHelper.dispatchTimeFromNow(semaphoreTimeout))
-        ex.publish("after close 2")
+        ex.publish("after close 2".dataUsingEncoding(NSUTF8StringEncoding))
         dispatch_semaphore_wait(semaphore, TestHelper.dispatchTimeFromNow(semaphoreTimeout))
 
-        XCTAssertEqual(["before close", "after close 1", "after close 2"], messages.map { $0.content })
+        XCTAssertEqual("before close".dataUsingEncoding(NSUTF8StringEncoding), messages[0].body)
+        XCTAssertEqual("after close 1".dataUsingEncoding(NSUTF8StringEncoding), messages[1].body)
+        XCTAssertEqual("after close 2".dataUsingEncoding(NSUTF8StringEncoding), messages[2].body)
 
         try! closeAllConnections()
 
         XCTAssert(TestHelper.pollUntil { delegate.recoveredConnection != nil },
                   "Didn't finish recovery the second time")
 
-        q.publish("after close 3")
+        q.publish("after close 3".dataUsingEncoding(NSUTF8StringEncoding))
         dispatch_semaphore_wait(semaphore, TestHelper.dispatchTimeFromNow(semaphoreTimeout))
-        ex.publish("after close 4")
+        ex.publish("after close 4".dataUsingEncoding(NSUTF8StringEncoding))
         dispatch_semaphore_wait(semaphore, TestHelper.dispatchTimeFromNow(semaphoreTimeout))
 
-        XCTAssertEqual(["before close", "after close 1", "after close 2", "after close 3", "after close 4"], messages.map { $0.content })
+        XCTAssertEqual("before close".dataUsingEncoding(NSUTF8StringEncoding), messages[0].body)
+        XCTAssertEqual("after close 1".dataUsingEncoding(NSUTF8StringEncoding), messages[1].body)
+        XCTAssertEqual("after close 2".dataUsingEncoding(NSUTF8StringEncoding), messages[2].body)
+        XCTAssertEqual("after close 3".dataUsingEncoding(NSUTF8StringEncoding), messages[3].body)
+        XCTAssertEqual("after close 4".dataUsingEncoding(NSUTF8StringEncoding), messages[4].body)
     }
 
     private func connections() -> [RMQHTTPConnection] {
diff --git a/RMQClientIntegrationTests/IntegrationTests.swift b/RMQClientIntegrationTests/IntegrationTests.swift
index 49a113b5..b0cecb76 100644
--- a/RMQClientIntegrationTests/IntegrationTests.swift
+++ b/RMQClientIntegrationTests/IntegrationTests.swift
@@ -88,11 +88,13 @@ class IntegrationTests: XCTestCase {
         dst.bind(src)
         q.bind(dst)
 
-        src.publish(messageContent)
+        let body = messageContent.dataUsingEncoding(NSUTF8StringEncoding)!
+
+        src.publish(body)
 
         let semaphore = dispatch_semaphore_create(0)
         let expected = RMQMessage(
-            content: messageContent,
+            body: body,
             consumerTag: "",
             deliveryTag: 1,
             redelivered: false,
@@ -146,14 +148,16 @@ class IntegrationTests: XCTestCase {
             dispatch_semaphore_signal(semaphore)
         }
 
-        q.publish("my message")
+        let body = "my message".dataUsingEncoding(NSUTF8StringEncoding)!
+
+        q.publish(body)
 
         XCTAssertEqual(0,
                        dispatch_semaphore_wait(semaphore, TestHelper.dispatchTimeFromNow(10)),
                        "Timed out waiting for message")
 
         XCTAssertEqual(1, delivered!.deliveryTag)
-        XCTAssertEqual("my message", delivered!.content)
+        XCTAssertEqual(body, delivered!.body)
     }
 
     func testMessageProperties() {
@@ -202,7 +206,7 @@ class IntegrationTests: XCTestCase {
             RMQBasicCorrelationId("r-1"),
             RMQBasicMessageId("m-1"),
             ]
-        q.publish("a message", properties: props, options: [])
+        q.publish("a message".dataUsingEncoding(NSUTF8StringEncoding), properties: props, options: [])
 
         XCTAssertEqual(0,
                        dispatch_semaphore_wait(semaphore, TestHelper.dispatchTimeFromNow(10)),
@@ -249,7 +253,7 @@ class IntegrationTests: XCTestCase {
             }
         }
 
-        ch.defaultExchange().publish("my message", routingKey: q.name)
+        ch.defaultExchange().publish("my message".dataUsingEncoding(NSUTF8StringEncoding), routingKey: q.name)
 
         XCTAssertEqual(0,
                        dispatch_semaphore_wait(semaphore, TestHelper.dispatchTimeFromNow(10)),
@@ -300,7 +304,7 @@ class IntegrationTests: XCTestCase {
         let producingQueue = producingChannel.queue(consumingQueue.name, options: [.AutoDelete, .Exclusive])
 
         for _ in 1...messageCount {
-            producingQueue.publish("hello")
+            producingQueue.publish("hello".dataUsingEncoding(NSUTF8StringEncoding))
         }
 
         XCTAssertEqual(0,
@@ -346,7 +350,7 @@ class IntegrationTests: XCTestCase {
         }
 
         for _ in 1...messageCount {
-            producingQueue.publish("hello")
+            producingQueue.publish("hello".dataUsingEncoding(NSUTF8StringEncoding))
         }
 
         XCTAssertEqual(
@@ -393,6 +397,6 @@ class IntegrationTests: XCTestCase {
     }
 
     private func causeServerChannelClose(ch: RMQChannel) {
-        ch.basicPublish("", routingKey: "a route that can't be found", exchange: "a non-existent exchange", properties: [], options: [])
+        ch.basicPublish("".dataUsingEncoding(NSUTF8StringEncoding)!, routingKey: "a route that can't be found", exchange: "a non-existent exchange", properties: [], options: [])
     }
 }
diff --git a/RMQClientIntegrationTests/PublisherConfirmationIntegrationTest.swift b/RMQClientIntegrationTests/PublisherConfirmationIntegrationTest.swift
index 5b281843..055a6f68 100644
--- a/RMQClientIntegrationTests/PublisherConfirmationIntegrationTest.swift
+++ b/RMQClientIntegrationTests/PublisherConfirmationIntegrationTest.swift
@@ -64,8 +64,8 @@ class PublisherConfirmationIntegrationTest: XCTestCase {
 
         let q = ch.queue("", options: [.AutoDelete, .Exclusive])
 
-        q.publish("message a")
-        q.publish("message b")
+        q.publish("message a".dataUsingEncoding(NSUTF8StringEncoding))
+        q.publish("message b".dataUsingEncoding(NSUTF8StringEncoding))
 
         var acked: Set<NSNumber> = []
         var nacked: Set<NSNumber> = []
diff --git a/RMQClientTests/ChannelSpy.swift b/RMQClientTests/ChannelSpy.swift
index 65a0c369..d3ba5a71 100644
--- a/RMQClientTests/ChannelSpy.swift
+++ b/RMQClientTests/ChannelSpy.swift
@@ -61,7 +61,7 @@
     var lastReceivedBasicGetOptions: RMQBasicGetOptions?
     var lastReceivedBasicGetCompletionHandler: RMQConsumerDeliveryHandler?
 
-    var lastReceivedBasicPublishMessage: String?
+    var lastReceivedBasicPublishMessage: NSData?
     var lastReceivedBasicPublishRoutingKey: String?
     var lastReceivedBasicPublishExchange: String?
     var lastReceivedBasicPublishProperties: Array<RMQValue>?
@@ -217,8 +217,8 @@
         lastReceivedBasicCancelConsumerTag = consumerTag
     }
 
-    func basicPublish(message: String, routingKey: String, exchange: String, properties: [RMQValue], options: RMQBasicPublishOptions) {
-        lastReceivedBasicPublishMessage = message
+    func basicPublish(body: NSData, routingKey: String, exchange: String, properties: [RMQValue], options: RMQBasicPublishOptions) {
+        lastReceivedBasicPublishMessage = body
         lastReceivedBasicPublishRoutingKey = routingKey
         lastReceivedBasicPublishExchange = exchange
         lastReceivedBasicPublishProperties = properties
diff --git a/RMQClientTests/ConsumeTest.swift b/RMQClientTests/ConsumeTest.swift
index a0bc4b1f..7a436d30 100644
--- a/RMQClientTests/ConsumeTest.swift
+++ b/RMQClientTests/ConsumeTest.swift
@@ -90,7 +90,7 @@ class ConsumeTest: XCTestCase {
             exchange: "my-exchange",
             options: [.Redelivered]
         )
-        let expectedMessage = RMQMessage(content: "Consumed!",
+        let expectedMessage = RMQMessage(body: "Consumed!".dataUsingEncoding(NSUTF8StringEncoding),
                                          consumerTag: "tag",
                                          deliveryTag: 456,
                                          redelivered: true,
diff --git a/RMQClientTests/PublisherConfirmationTest.swift b/RMQClientTests/PublisherConfirmationTest.swift
index b21b4581..cd6db969 100644
--- a/RMQClientTests/PublisherConfirmationTest.swift
+++ b/RMQClientTests/PublisherConfirmationTest.swift
@@ -92,7 +92,7 @@ class PublisherConfirmationTest: XCTestCase {
         let ch = ChannelHelper.makeChannel(1, confirmations: confirmations)
 
         XCTAssertEqual(0, confirmations.publicationCount)
-        ch.basicPublish("hi there", routingKey: "", exchange: "", properties: [], options: [])
+        ch.basicPublish("hi there".dataUsingEncoding(NSUTF8StringEncoding)!, routingKey: "", exchange: "", properties: [], options: [])
         XCTAssertEqual(1, confirmations.publicationCount)
     }
 
diff --git a/RMQClientTests/RMQAllocatedChannelTest.swift b/RMQClientTests/RMQAllocatedChannelTest.swift
index 3198d97d..e0fc74af 100644
--- a/RMQClientTests/RMQAllocatedChannelTest.swift
+++ b/RMQClientTests/RMQAllocatedChannelTest.swift
@@ -189,7 +189,7 @@ class RMQAllocatedChannelTest: XCTestCase {
             contentBodies: [RMQContentBody(data: "hello".dataUsingEncoding(NSUTF8StringEncoding)!)]
         )
         let expectedMessage = RMQMessage(
-            content: "hello",
+            body: "hello".dataUsingEncoding(NSUTF8StringEncoding),
             consumerTag: "",
             deliveryTag: 1,
             redelivered: true,
@@ -224,8 +224,8 @@ class RMQAllocatedChannelTest: XCTestCase {
         let deliverHeader2 = RMQContentHeader(classID: deliverMethod2.classID(), bodySize: 123, properties: [])
         let deliverBody2 = RMQContentBody(data: "A message for consumer 2".dataUsingEncoding(NSUTF8StringEncoding)!)
         let deliverFrameset2 = RMQFrameset(channelNumber: 999, method: deliverMethod2, contentHeader: deliverHeader2, contentBodies: [deliverBody2])
-        let expectedMessage1 = RMQMessage(content: "A message for consumer 1", consumerTag: "tag1", deliveryTag: 1, redelivered: false, exchangeName: "", routingKey: "", properties: [])
-        let expectedMessage2 = RMQMessage(content: "A message for consumer 2", consumerTag: "tag2", deliveryTag: 1, redelivered: false, exchangeName: "", routingKey: "", properties: [])
+        let expectedMessage1 = RMQMessage(body: "A message for consumer 1".dataUsingEncoding(NSUTF8StringEncoding), consumerTag: "tag1", deliveryTag: 1, redelivered: false, exchangeName: "", routingKey: "", properties: [])
+        let expectedMessage2 = RMQMessage(body: "A message for consumer 2".dataUsingEncoding(NSUTF8StringEncoding), consumerTag: "tag2", deliveryTag: 1, redelivered: false, exchangeName: "", routingKey: "", properties: [])
 
         ch.activateWithDelegate(nil)
 
@@ -256,7 +256,7 @@ class RMQAllocatedChannelTest: XCTestCase {
     func testBasicPublishSendsAsyncFrameset() {
         let dispatcher = DispatcherSpy()
         let ch = ChannelHelper.makeChannel(999, contentBodySize: 4, dispatcher: dispatcher)
-        let message = "my great message yo"
+        let message = "my great message yo".dataUsingEncoding(NSUTF8StringEncoding)!
         let notPersistent = RMQBasicDeliveryMode(1)
         let customContentType = RMQBasicContentType("my/content-type")
         let priorityZero = RMQBasicPriority(0)
@@ -264,7 +264,7 @@ class RMQAllocatedChannelTest: XCTestCase {
         let expectedMethod = MethodFixtures.basicPublish("my.q", exchange: "", options: [.Mandatory])
         let expectedHeader = RMQContentHeader(
             classID: 60,
-            bodySize: message.dataUsingEncoding(NSUTF8StringEncoding)!.length,
+            bodySize: message.length,
             properties: [notPersistent, customContentType, priorityZero]
         )
         let expectedBodies = [
@@ -295,7 +295,7 @@ class RMQAllocatedChannelTest: XCTestCase {
         let ch = ChannelHelper.makeChannel(999, contentBodySize: 4, dispatcher: dispatcher)
 
         let props: [RMQValue] = [RMQBasicCorrelationId("my-correlation-id")]
-        ch.basicPublish("", routingKey: "", exchange: "", properties: props, options: [])
+        ch.basicPublish(NSData(), routingKey: "", exchange: "", properties: props, options: [])
 
         let expectedProperties: Set<RMQValue> = Set(RMQBasicProperties.defaultProperties()).union(props)
         let header = dispatcher.lastAsyncFrameset!.contentHeader
@@ -306,9 +306,9 @@ class RMQAllocatedChannelTest: XCTestCase {
     func testPublishWhenContentLengthIsMultipleOfFrameMax() {
         let dispatcher = DispatcherSpy()
         let ch = ChannelHelper.makeChannel(999, contentBodySize: 4, dispatcher: dispatcher)
-        let messageContent = "12345678"
+        let messageContent = "12345678".dataUsingEncoding(NSUTF8StringEncoding)!
         let expectedMethod = MethodFixtures.basicPublish("my.q", exchange: "", options: [])
-        let expectedBodyData = messageContent.dataUsingEncoding(NSUTF8StringEncoding)!
+        let expectedBodyData = messageContent
         let expectedHeader = RMQContentHeader(
             classID: 60,
             bodySize: expectedBodyData.length,
diff --git a/RMQClientTests/RMQExchangeTest.swift b/RMQClientTests/RMQExchangeTest.swift
index df6bf435..10af36f2 100644
--- a/RMQClientTests/RMQExchangeTest.swift
+++ b/RMQClientTests/RMQExchangeTest.swift
@@ -53,12 +53,14 @@ import XCTest
 
 class RMQExchangeTest: XCTestCase {
 
+    let body = "foo".dataUsingEncoding(NSUTF8StringEncoding)!
+
     func testPublishCallsPublishOnChannel() {
         let ch = ChannelSpy(1)
         let ex = RMQExchange(name: "", type: "direct", options: [], channel: ch)
-        ex.publish("foo", routingKey: "my.q")
+        ex.publish(body, routingKey: "my.q")
 
-        XCTAssertEqual("foo", ch.lastReceivedBasicPublishMessage)
+        XCTAssertEqual(body, ch.lastReceivedBasicPublishMessage)
         XCTAssertEqual("my.q", ch.lastReceivedBasicPublishRoutingKey)
         XCTAssertEqual("", ch.lastReceivedBasicPublishExchange)
         XCTAssertEqual([], ch.lastReceivedBasicPublishProperties!)
@@ -68,7 +70,7 @@ class RMQExchangeTest: XCTestCase {
     func testPublishWithoutRoutingKeyUsesEmptyString() {
         let ch = ChannelSpy(1)
         let ex = RMQExchange(name: "", type: "direct", options: [], channel: ch)
-        ex.publish("foo")
+        ex.publish(body)
 
         XCTAssertEqual("", ch.lastReceivedBasicPublishRoutingKey)
     }
@@ -76,9 +78,9 @@ class RMQExchangeTest: XCTestCase {
     func testPublishWithPersistence() {
         let ch = ChannelSpy(1)
         let ex = RMQExchange(name: "some-ex", type: "direct", options: [], channel: ch)
-        ex.publish("foo", routingKey: "my.q", persistent: true)
+        ex.publish(body, routingKey: "my.q", persistent: true)
 
-        XCTAssertEqual("foo", ch.lastReceivedBasicPublishMessage)
+        XCTAssertEqual(body, ch.lastReceivedBasicPublishMessage)
         XCTAssertEqual("my.q", ch.lastReceivedBasicPublishRoutingKey)
         XCTAssertEqual("some-ex", ch.lastReceivedBasicPublishExchange)
         XCTAssertEqual([RMQBasicDeliveryMode(2)], ch.lastReceivedBasicPublishProperties!)
@@ -106,12 +108,12 @@ class RMQExchangeTest: XCTestCase {
             BasicPropertyFixtures.exhaustiveHeaders()
         ]
 
-        ex.publish("{\"a\": \"message\"}",
+        ex.publish("{\"a\": \"message\"}".dataUsingEncoding(NSUTF8StringEncoding),
                    routingKey: "some.queue",
                    properties: properties,
                    options: [.Mandatory])
 
-        XCTAssertEqual("{\"a\": \"message\"}", channel.lastReceivedBasicPublishMessage)
+        XCTAssertEqual("{\"a\": \"message\"}".dataUsingEncoding(NSUTF8StringEncoding), channel.lastReceivedBasicPublishMessage)
         XCTAssertEqual("some.queue", channel.lastReceivedBasicPublishRoutingKey)
         XCTAssertEqual("some-ex", channel.lastReceivedBasicPublishExchange)
         XCTAssertEqual([.Mandatory], channel.lastReceivedBasicPublishOptions)
@@ -121,9 +123,9 @@ class RMQExchangeTest: XCTestCase {
     func testPublishWithOptions() {
         let ch = ChannelSpy(1)
         let ex = RMQExchange(name: "some-ex", type: "direct", options: [], channel: ch)
-        ex.publish("foo", routingKey: "my.q", persistent: false, options: [.Mandatory])
+        ex.publish(body, routingKey: "my.q", persistent: false, options: [.Mandatory])
 
-        XCTAssertEqual("foo", ch.lastReceivedBasicPublishMessage)
+        XCTAssertEqual(body, ch.lastReceivedBasicPublishMessage)
         XCTAssertEqual("my.q", ch.lastReceivedBasicPublishRoutingKey)
         XCTAssertEqual("some-ex", ch.lastReceivedBasicPublishExchange)
         XCTAssertEqual([], ch.lastReceivedBasicPublishProperties!)
diff --git a/RMQClientTests/RMQMessageTest.swift b/RMQClientTests/RMQMessageTest.swift
index f63cbcc6..810cdcb6 100644
--- a/RMQClientTests/RMQMessageTest.swift
+++ b/RMQClientTests/RMQMessageTest.swift
@@ -66,7 +66,7 @@ class RMQMessageTest: XCTestCase {
         props.append(RMQBasicReplyTo("my.sender"))
         props.append(RMQBasicTimestamp(date))
 
-        let m = RMQMessage(content: "my message",
+        let m = RMQMessage(body: "my message".dataUsingEncoding(NSUTF8StringEncoding),
                            consumerTag: "ctag",
                            deliveryTag: 1,
                            redelivered: false,
diff --git a/RMQClientTests/RMQQueueTest.swift b/RMQClientTests/RMQQueueTest.swift
index 41accb6a..11566f92 100644
--- a/RMQClientTests/RMQQueueTest.swift
+++ b/RMQClientTests/RMQQueueTest.swift
@@ -52,13 +52,14 @@
 import XCTest
 
 class RMQQueueTest: XCTestCase {
+    let body = "a message".dataUsingEncoding(NSUTF8StringEncoding)!
     func testPublishSendsBasicPublishToChannel() {
         let channel = ChannelSpy(42)
         let queue = QueueHelper.makeQueue(channel, name: "some.queue")
 
-        queue.publish("a message")
+        queue.publish(body)
 
-        XCTAssertEqual("a message", channel.lastReceivedBasicPublishMessage)
+        XCTAssertEqual(body, channel.lastReceivedBasicPublishMessage)
         XCTAssertEqual("some.queue", channel.lastReceivedBasicPublishRoutingKey)
         XCTAssertEqual("", channel.lastReceivedBasicPublishExchange)
         XCTAssertEqual([], channel.lastReceivedBasicPublishProperties!)
@@ -69,9 +70,9 @@ class RMQQueueTest: XCTestCase {
         let channel = ChannelSpy(42)
         let queue = QueueHelper.makeQueue(channel, name: "some.queue")
 
-        queue.publish("a message", persistent: true)
+        queue.publish(body, persistent: true)
 
-        XCTAssertEqual("a message", channel.lastReceivedBasicPublishMessage)
+        XCTAssertEqual(body, channel.lastReceivedBasicPublishMessage)
         XCTAssertEqual("some.queue", channel.lastReceivedBasicPublishRoutingKey)
         XCTAssertEqual("", channel.lastReceivedBasicPublishExchange)
         XCTAssertEqual([RMQBasicDeliveryMode(2)], channel.lastReceivedBasicPublishProperties!)
@@ -99,11 +100,11 @@ class RMQQueueTest: XCTestCase {
             BasicPropertyFixtures.exhaustiveHeaders()
         ]
 
-        queue.publish("{\"a\": \"message\"}",
+        queue.publish("{\"a\": \"message\"}".dataUsingEncoding(NSUTF8StringEncoding),
                       properties: properties,
                       options: [.Mandatory])
 
-        XCTAssertEqual("{\"a\": \"message\"}", channel.lastReceivedBasicPublishMessage)
+        XCTAssertEqual("{\"a\": \"message\"}".dataUsingEncoding(NSUTF8StringEncoding), channel.lastReceivedBasicPublishMessage)
         XCTAssertEqual("some.queue", channel.lastReceivedBasicPublishRoutingKey)
         XCTAssertEqual("", channel.lastReceivedBasicPublishExchange)
         XCTAssertEqual([.Mandatory], channel.lastReceivedBasicPublishOptions)
@@ -114,9 +115,9 @@ class RMQQueueTest: XCTestCase {
         let channel = ChannelSpy(42)
         let queue = QueueHelper.makeQueue(channel, name: "some.queue")
 
-        queue.publish("a message", persistent: false, options: [.Mandatory])
+        queue.publish(body, persistent: false, options: [.Mandatory])
 
-        XCTAssertEqual("a message", channel.lastReceivedBasicPublishMessage)
+        XCTAssertEqual(body, channel.lastReceivedBasicPublishMessage)
         XCTAssertEqual("some.queue", channel.lastReceivedBasicPublishRoutingKey)
         XCTAssertEqual("", channel.lastReceivedBasicPublishExchange)
         XCTAssertEqual([], channel.lastReceivedBasicPublishProperties!)
@@ -124,7 +125,7 @@ class RMQQueueTest: XCTestCase {
     }
 
     func testPopDelegatesToChannelBasicGet() {
-        let stubbedMessage = RMQMessage(content: "hi there", consumerTag: "", deliveryTag: 123, redelivered: false, exchangeName: "", routingKey: "", properties: [])
+        let stubbedMessage = RMQMessage(body: body, consumerTag: "", deliveryTag: 123, redelivered: false, exchangeName: "", routingKey: "", properties: [])
         let channel = ChannelSpy(42)
         let queue = QueueHelper.makeQueue(channel, name: "great.queue")
 
@@ -149,7 +150,7 @@ class RMQQueueTest: XCTestCase {
             handlerCalled = true
         }
 
-        let message = RMQMessage(content: "I have default options!", consumerTag: "", deliveryTag: 123, redelivered: false, exchangeName: "", routingKey: "", properties: [])
+        let message = RMQMessage(body: "I have default options!".dataUsingEncoding(NSUTF8StringEncoding), consumerTag: "", deliveryTag: 123, redelivered: false, exchangeName: "", routingKey: "", properties: [])
         channel.lastReceivedBasicConsumeBlock!(message)
 
         XCTAssert(handlerCalled)
@@ -165,7 +166,7 @@ class RMQQueueTest: XCTestCase {
             handlerCalled = true
         }
 
-        let message = RMQMessage(content: "I have custom options!", consumerTag: "", deliveryTag: 123, redelivered: false, exchangeName: "", routingKey: "", properties: [])
+        let message = RMQMessage(body: "I have custom options!".dataUsingEncoding(NSUTF8StringEncoding), consumerTag: "", deliveryTag: 123, redelivered: false, exchangeName: "", routingKey: "", properties: [])
         channel.lastReceivedBasicConsumeBlock!(message)
 
         XCTAssert(handlerCalled)
diff --git a/RMQClientTests/RMQUnallocatedChannelTest.swift b/RMQClientTests/RMQUnallocatedChannelTest.swift
index 21f98451..db3aad50 100644
--- a/RMQClientTests/RMQUnallocatedChannelTest.swift
+++ b/RMQClientTests/RMQUnallocatedChannelTest.swift
@@ -69,7 +69,7 @@ class RMQUnallocatedChannelTest: XCTestCase {
             { ch.afterConfirmed { _ in } },
             { ch.basicConsume("foo", options: []) { _ in } },
             { ch.basicGet("foo", options: []) { _ in } },
-            { ch.basicPublish("hi", routingKey: "yo", exchange: "hmm", properties: [], options: []) },
+            { ch.basicPublish("hi".dataUsingEncoding(NSUTF8StringEncoding)!, routingKey: "yo", exchange: "hmm", properties: [], options: []) },
             { ch.basicQos(2, global: false) },
             { ch.blockingWaitOn(RMQConnectionStart.self) },
             { ch.confirmSelect() },