diff --git a/stacker/actions/build.py b/stacker/actions/build.py
index a88994b09..a1bfbb138 100644
--- a/stacker/actions/build.py
+++ b/stacker/actions/build.py
@@ -87,6 +87,7 @@ def resolve_parameters(parameters, blueprint, context, provider):
             v_list = []
             values = value.split(',')
             for v in values:
+                v = v.strip()
                 stack_name, output = v.split('::')
                 stack_fqn = context.get_fqn(stack_name)
                 try:
diff --git a/stacker/tests/actions/test_build.py b/stacker/tests/actions/test_build.py
index 1bd67df38..576b8da12 100644
--- a/stacker/tests/actions/test_build.py
+++ b/stacker/tests/actions/test_build.py
@@ -40,7 +40,6 @@ def get_outputs(self, stack_name, *args, **kwargs):
 
 
 class TestBuildAction(unittest.TestCase):
-
     def setUp(self):
         self.context = Context({'namespace': 'namespace'})
         self.build_action = build.Action(self.context, provider=TestProvider())
@@ -308,6 +307,14 @@ def get_output(stack, param):
         self.assertEqual(p["a"], "Apple,Carrot")
         self.assertEqual(p["b"], "Banana")
 
+        # Test multi-output with spaces
+        params = {"a": "other-stack::a, other-stack::c", "b": "Banana"}
+        self.prov.get_output.side_effect = get_output
+        p = resolve_parameters(params, self.bp, self.ctx, self.prov)
+        self.assertEqual(self.prov.get_output.call_count, 4)
+        self.assertEqual(p["a"], "Apple,Carrot")
+        self.assertEqual(p["b"], "Banana")
+
     def test_resolve_parameters_output_does_not_exist(self):
         def get_output(stack, param):
             d = {'c': 'Carrot'}