diff --git a/tests/runner.lua b/tests/runner.lua
index 029aae1..155b1d5 100644
--- a/tests/runner.lua
+++ b/tests/runner.lua
@@ -56,7 +56,8 @@ if arg[1] then
 else
   local files = {
     'observer',
-    'observable'
+    'observable',
+    'subscription'
   }
 
   for i, file in ipairs(files) do
diff --git a/tests/subscription.lua b/tests/subscription.lua
new file mode 100644
index 0000000..199f379
--- /dev/null
+++ b/tests/subscription.lua
@@ -0,0 +1,26 @@
+describe('Subscription', function()
+  describe('create', function()
+    it('returns a Subscription', function()
+      local subscription = Rx.Subscription.create()
+      expect(subscription).to.be.an(Rx.Subscription)
+    end)
+  end)
+
+  describe('unsubscribe', function()
+    it('runs the function passed to create', function()
+      local unsubscribe = spy()
+      local subscription = Rx.Subscription.create(unsubscribe)
+      subscription:unsubscribe()
+      expect(#unsubscribe).to.equal(1)
+    end)
+
+    it('does not run the function passed to create more than once', function()
+      local unsubscribe = spy()
+      local subscription = Rx.Subscription.create(unsubscribe)
+      subscription:unsubscribe()
+      subscription:unsubscribe()
+      subscription:unsubscribe()
+      expect(#unsubscribe).to.equal(1)
+    end)
+  end)
+end)