diff --git a/rds/example/parameter_group_provided.tf b/rds/example/parameter_group_provided.tf
new file mode 100644
index 0000000..6f22f70
--- /dev/null
+++ b/rds/example/parameter_group_provided.tf
@@ -0,0 +1,17 @@
+module "rds-parameter-group-provided" {
+  source = "../"
+
+  engine = "postgres"
+  name = "rds-parameter-group-provided"
+  parameter_group_name = "${aws_db_parameter_group.parameter-group-provided.id}"
+  parameter_group_provided = true
+  subnets = ["rds-parameter-group-provided"]
+  version = "9.6"
+  vpc_id = "rds-parameter-group-provided"
+}
+
+resource "aws_db_parameter_group" "parameter-group-provided" {
+  name = "parameter-group-provided"
+  family = "parameter-group-provided"
+  description = "parameter-group-provided"
+}
diff --git a/rds/main.tf b/rds/main.tf
index 442dc28..9e20ceb 100644
--- a/rds/main.tf
+++ b/rds/main.tf
@@ -27,7 +27,7 @@ resource "aws_db_subnet_group" "mod" {
 }
 
 resource "aws_db_parameter_group" "mod" {
-  count = "${var.parameter_group_name != "" ? 0 : 1}"
+  count = "${var.parameter_group_provided ? 0 : 1}"
   name = "${local.parameter_group_name}"
   family = "${local.family}"
   description = "${local.family} parameter group for ${var.name} ${var.env}"
diff --git a/rds/variables.tf b/rds/variables.tf
index 18ea7ce..0ee08d5 100644
--- a/rds/variables.tf
+++ b/rds/variables.tf
@@ -52,6 +52,11 @@ variable "parameter_group_name" {
   default = ""
 }
 
+variable "parameter_group_provided" {
+  description = "If the parameter_group_name is provided, must be set to true."
+  default = false
+}
+
 variable "port" {
   description = "Override the default port"
   default = ""