relationship -> relationships
diff --git a/xos/tosca/resources/xossite.py b/xos/tosca/resources/xossite.py
index a65129a..997c9e9 100644
--- a/xos/tosca/resources/xossite.py
+++ b/xos/tosca/resources/xossite.py
@@ -46,7 +46,7 @@
                     controller_name = None
                     for sd_req in v["requirements"]:
                         for (sd_req_k, sd_req_v) in sd_req.items():
-                            if sd_req_v["relationship"] == "tosca.relationship.UsesController":
+                            if sd_req_v["relationship"] == "tosca.relationships.UsesController":
                                 controller_name = sd_req_v["node"]
                     if not controller_name:
                         raise Exception("Controller must be specified in SiteDeployment relationship")
diff --git a/xos/tosca/samples/new_site_deploy_slice.yaml b/xos/tosca/samples/new_site_deploy_slice.yaml
index fa047a3..6ccadc1 100644
--- a/xos/tosca/samples/new_site_deploy_slice.yaml
+++ b/xos/tosca/samples/new_site_deploy_slice.yaml
@@ -40,7 +40,7 @@
                requirements:
                    - controller:
                        node: newcontroller
-                       relationship: tosca.relationship.UsesController
+                       relationship: tosca.relationships.UsesController
 
     newsite_tosca:
       type: tosca.nodes.Slice