diff --git a/lib/terraforming/cli.rb b/lib/terraforming/cli.rb
index <HASH>..<HASH> 100644
--- a/lib/terraforming/cli.rb
+++ b/lib/terraforming/cli.rb
@@ -43,6 +43,11 @@ module Terraforming
       execute(Terraforming::Resource::IAMGroup, options)
     end
 
+    desc "iamgm", "IAM Group Membership"
+    def iamgm
+      execute(Terraforming::Resource::IAMGroupMembership, options)
+    end
+
     desc "iamgp", "IAM Group Policy"
     def iamgp
       execute(Terraforming::Resource::IAMGroupPolicy, options)
diff --git a/spec/lib/terraforming/cli_spec.rb b/spec/lib/terraforming/cli_spec.rb
index <HASH>..<HASH> 100644
--- a/spec/lib/terraforming/cli_spec.rb
+++ b/spec/lib/terraforming/cli_spec.rb
@@ -81,6 +81,13 @@ module Terraforming
       it_behaves_like "CLI examples"
     end
 
+    describe "iamgm" do
+      let(:klass)   { Terraforming::Resource::IAMGroupMembership }
+      let(:command) { :iamgm }
+
+      it_behaves_like "CLI examples"
+    end
+
     describe "iamgp" do
       let(:klass)   { Terraforming::Resource::IAMGroupPolicy }
       let(:command) { :iamgp }
Define CLI command iamgm for IAM Group Membership