diff --git a/dev/cljs/wish/config.cljs b/dev/cljs/wish/config.cljs
index 090f5424..ed61b5f3 100644
--- a/dev/cljs/wish/config.cljs
+++ b/dev/cljs/wish/config.cljs
@@ -8,6 +8,7 @@
   ^boolean goog.DEBUG)
 
 (def server-root "")
+(def full-url-root (str "http://localhost:3450" server-root))
 
 (def gdrive-client-id "661182319990-1uerkr0pue6k60a83atj2f58md95fb1b.apps.googleusercontent.com")
 
diff --git a/less/site.less b/less/site.less
index f993ae80..5db96c59 100644
--- a/less/site.less
+++ b/less/site.less
@@ -320,6 +320,10 @@ a {
 //
 // Campaign screen widgets
 
+.add-chars-overlay {
+    padding: 32px;
+}
+
 .carousel-container {
     width: 100%;
     overflow-x: auto;
@@ -327,6 +331,14 @@ a {
     .carousel {
         .flex();
 
+        a.add-button {
+            .flex();
+            .flex-direction(row);
+            .align-items(center);
+
+            padding: 8px;
+        }
+
         a.card {
             color: inherit;
             margin: 8px 4px;
diff --git a/prod/cljs/wish/config.cljs b/prod/cljs/wish/config.cljs
index bd4d5353..5470a037 100644
--- a/prod/cljs/wish/config.cljs
+++ b/prod/cljs/wish/config.cljs
@@ -9,6 +9,9 @@
 ; IE: https://dhleong.github.io/wish
 (def server-root "/wish")
 
+; TODO good-define?
+(def full-url-root (str "https://dhleong.github.io" server-root))
+
 (def gdrive-client-id "661182319990-3aa8akj9fh8eva9lf7bt02621q2i18s6.apps.googleusercontent.com")
 
 (def push-server "https://wish-server.now.sh")
diff --git a/src/cljs/wish/routes.cljs b/src/cljs/wish/routes.cljs
index 3848c41a..78ac5a5b 100644
--- a/src/cljs/wish/routes.cljs
+++ b/src/cljs/wish/routes.cljs
@@ -21,6 +21,9 @@
   (defroute #"/campaigns/([a-z0-9-]+/[^/]+)" [id]
     (navigate! :campaign [(keyword id)]))
 
+  (defroute #"/join-campaign/([a-z0-9-]+/[^/]+)/as/(.*)" [campaign-id sheet-id]
+    (navigate! :join-campaign [(keyword campaign-id) (keyword sheet-id)]))
+
   (defroute "/sheets" []
     (navigate! :sheet-browser))
 
diff --git a/src/cljs/wish/subs.cljs b/src/cljs/wish/subs.cljs
index 156b002a..4198975d 100644
--- a/src/cljs/wish/subs.cljs
+++ b/src/cljs/wish/subs.cljs
@@ -100,6 +100,7 @@
 (reg-sub :sheet-sources :sheet-sources)
 
 ; sheets
+(reg-meta-sub :meta/name :name)
 (reg-meta-sub :meta/sheet :sheet)
 (reg-meta-sub :meta/sources :sources)
 (reg-meta-sub :meta/kind :kind)
@@ -718,6 +719,17 @@
 
 
 ; ======= Campaign-related ================================
+; TODO can these be broken out to a separate file?
+
+(reg-sub
+  :campaign-add-char-candidates
+  :<- [:meta/players]
+  :<- [:known-sheets]
+  (fn [[current-members sheets]]
+    (->> sheets
+         (remove :mine?)
+         (remove (comp current-members :id))
+         )))
 
 (reg-sub
   :campaign-members
diff --git a/src/cljs/wish/util/nav.cljs b/src/cljs/wish/util/nav.cljs
index 2f395110..35c64462 100644
--- a/src/cljs/wish/util/nav.cljs
+++ b/src/cljs/wish/util/nav.cljs
@@ -8,6 +8,7 @@
             [goog.events :as gevents]
             [goog.history.EventType :as HistoryEventType]
             [pushy.core :as pushy]
+            [wish.config :as config]
             [wish.util :refer [is-ios? >evt]])
   (:import goog.History))
 
@@ -108,6 +109,16 @@
   [id & extra-sections]
   (apply base-sheet-url "campaigns" id extra-sections))
 
+(defn campaign-invite-url
+  "Generate the url to join a campaign"
+  [campaign-id invited-sheet-url]
+  (str
+    config/full-url-root
+    (prefix
+      (base-sheet-url "join-campaign" campaign-id
+                      "as"
+                      (namespace invited-sheet-url) invited-sheet-url))))
+
 (defn sheet-url
   "Generate the url to a sheet, optionally with
    extra path sections after it"
diff --git a/src/cljs/wish/views.cljs b/src/cljs/wish/views.cljs
index 8a27ff98..440d181d 100644
--- a/src/cljs/wish/views.cljs
+++ b/src/cljs/wish/views.cljs
@@ -8,6 +8,8 @@
    [wish.util :refer [<sub click>evt]]
    [wish.views.error-boundary :refer [error-boundary]]
    [wish.views.campaign-browser :as campaign-browser]
+   [wish.views.campaign.join :as join-campaign]
+   [wish.views.error-boundary :refer [error-boundary]]
    [wish.views.home :refer [home]]
    [wish.views.new-campaign :as new-campaign]
    [wish.views.new-sheet :refer [new-sheet-page]]
@@ -23,6 +25,7 @@
   {:campaign #'sheets/campaign
    :campaign-browser #'campaign-browser/page
    :home #'home
+   :join-campaign #'join-campaign/page
    :new-campaign #'new-campaign/page
    :new-sheet #'new-sheet-page
    :sheet #'sheets/viewer
diff --git a/src/cljs/wish/views/campaign/base.cljs b/src/cljs/wish/views/campaign/base.cljs
index 5dc2fedb..e53cf035 100644
--- a/src/cljs/wish/views/campaign/base.cljs
+++ b/src/cljs/wish/views/campaign/base.cljs
@@ -1,10 +1,12 @@
 (ns ^{:author "Daniel Leong"
       :doc "base"}
   wish.views.campaign.base
-  (:require [wish.views.campaign.chars-carousel :refer [chars-carousel]]))
+  (:require [wish.views.campaign.chars-carousel :refer [chars-carousel]]
+            [wish.views.error-boundary :refer [error-boundary]]))
 
 (defn campaign-page
   [section & {:keys [char-card]}]
-  [:div.campaign
-   [chars-carousel char-card]
-   "TODO campaign"])
+  [error-boundary
+   [:div.campaign
+    [chars-carousel char-card]
+    "TODO campaign"]])
diff --git a/src/cljs/wish/views/campaign/chars_carousel.cljs b/src/cljs/wish/views/campaign/chars_carousel.cljs
index 107d901c..e8fb38a3 100644
--- a/src/cljs/wish/views/campaign/chars_carousel.cljs
+++ b/src/cljs/wish/views/campaign/chars_carousel.cljs
@@ -2,9 +2,9 @@
       :doc "campaign.chars-carousel"}
   wish.views.campaign.chars-carousel
   (:require [wish.util :refer [<sub >evt]]
-            [wish.util.nav :refer [sheet-url]]
+            [wish.util.nav :as nav :refer [sheet-url]]
             [wish.views.error-boundary :refer [error-boundary]]
-            [wish.views.widgets :refer [link]]))
+            [wish.views.widgets :refer [icon link link>evt]]))
 
 (defn- sheet-loader [sheet]
   [:div "Loading " (:name sheet) "..."])
@@ -31,11 +31,46 @@
         (>evt [:load-sheet! sheet-id])
         [sheet-loader sheet]))))
 
+(defn add-chars-overlay []
+  (let [campaign-id (<sub [:active-sheet-id])]
+    [:div.add-chars-overlay
+     [:div.title
+      "Add characters to "
+      (<sub [:meta/name])]
+
+     [:div.candidates
+      (for [c (<sub [:campaign-members])]
+        ^{:key (:id c)}
+        [:div.character
+         (:name c)
+
+         [:input.invite-url
+          {:type :text
+           :value (nav/campaign-invite-url
+                    campaign-id
+                    (:id c))}
+          ]
+         ])
+
+      (for [c (<sub [:campaign-add-char-candidates])]
+        ^{:key (:id c)}
+        [:div.character
+         (:name c)
+
+         [:div
+          "INVITE (todo)"]
+         ])]
+     ]))
+
 (defn chars-carousel [chars-card-view]
   (if-let [members (seq (<sub [:campaign-members]))]
     [:div.carousel-container
      [:div.carousel
 
+      [link>evt {:> [:toggle-overlay [#'add-chars-overlay]]
+                 :class "add-button"}
+       (icon :add)]
+
       (for [c members]
         ^{:key (:id c)}
         [link {:href (sheet-url (:id c))
diff --git a/src/cljs/wish/views/campaign/join.cljs b/src/cljs/wish/views/campaign/join.cljs
new file mode 100644
index 00000000..9e131513
--- /dev/null
+++ b/src/cljs/wish/views/campaign/join.cljs
@@ -0,0 +1,6 @@
+(ns ^{:author "Daniel Leong"
+      :doc "Join a campaign as a player"}
+  wish.views.campaign.join)
+
+(defn page [campaign-id sheet-id]
+  [:div "TODO"])