diff --git a/pkg/apis/servicecatalog/validation/instance_test.go b/pkg/apis/servicecatalog/validation/instance_test.go
index 7dd80571c6b..cb691314686 100644
--- a/pkg/apis/servicecatalog/validation/instance_test.go
+++ b/pkg/apis/servicecatalog/validation/instance_test.go
@@ -114,6 +114,15 @@ func TestValidateServiceInstance(t *testing.T) {
 			instance: validServiceInstance(),
 			valid:    true,
 		},
+		{
+			name: "valid planName",
+			instance: func() *servicecatalog.ServiceInstance {
+				i := validServiceInstance()
+				i.Spec.ClusterServicePlanExternalName = "9651.JVHbebe"
+				return i
+			}(),
+			valid: true,
+		},
 		{
 			name: "missing namespace",
 			instance: func() *servicecatalog.ServiceInstance {
@@ -154,7 +163,7 @@ func TestValidateServiceInstance(t *testing.T) {
 			name: "invalid planName",
 			instance: func() *servicecatalog.ServiceInstance {
 				i := validServiceInstance()
-				i.Spec.ClusterServicePlanExternalName = "9651.JVHbebe"
+				i.Spec.ClusterServicePlanExternalName = "9651_JVHbebe"
 				return i
 			}(),
 			valid: false,
diff --git a/pkg/apis/servicecatalog/validation/serviceclass.go b/pkg/apis/servicecatalog/validation/serviceclass.go
index 21185c73935..50311f0dff1 100644
--- a/pkg/apis/servicecatalog/validation/serviceclass.go
+++ b/pkg/apis/servicecatalog/validation/serviceclass.go
@@ -26,7 +26,7 @@ import (
 	sc "github.com/kubernetes-incubator/service-catalog/pkg/apis/servicecatalog"
 )
 
-const serviceClassNameFmt string = `[-a-zA-Z0-9]+`
+const serviceClassNameFmt string = `[-.a-zA-Z0-9]+`
 const serviceClassNameMaxLength int = 63
 
 var serviceClassNameRegexp = regexp.MustCompile("^" + serviceClassNameFmt + "$")
diff --git a/pkg/apis/servicecatalog/validation/serviceclass_test.go b/pkg/apis/servicecatalog/validation/serviceclass_test.go
index 17dacf5aa9f..6d96bf6bdf5 100644
--- a/pkg/apis/servicecatalog/validation/serviceclass_test.go
+++ b/pkg/apis/servicecatalog/validation/serviceclass_test.go
@@ -68,6 +68,15 @@ func TestValidateClusterServiceClass(t *testing.T) {
 			}(),
 			valid: true,
 		},
+		{
+			name: "valid serviceClass - period in externalName",
+			serviceClass: func() *servicecatalog.ClusterServiceClass {
+				s := validClusterServiceClass()
+				s.Spec.ExternalName = "abc.com"
+				return s
+			}(),
+			valid: true,
+		},
 		{
 			name: "invalid serviceClass - has namespace",
 			serviceClass: func() *servicecatalog.ClusterServiceClass {
@@ -114,10 +123,10 @@ func TestValidateClusterServiceClass(t *testing.T) {
 			valid: false,
 		},
 		{
-			name: "invalid serviceClass - period in externalName",
+			name: "invalid serviceClass - underscore in externalName",
 			serviceClass: func() *servicecatalog.ClusterServiceClass {
 				s := validClusterServiceClass()
-				s.Spec.ExternalName = "abc.com"
+				s.Spec.ExternalName = "test_serviceclass"
 				return s
 			}(),
 			valid: false,
diff --git a/pkg/apis/servicecatalog/validation/serviceplan.go b/pkg/apis/servicecatalog/validation/serviceplan.go
index 7acdb267b2c..06079299bad 100644
--- a/pkg/apis/servicecatalog/validation/serviceplan.go
+++ b/pkg/apis/servicecatalog/validation/serviceplan.go
@@ -26,7 +26,7 @@ import (
 	sc "github.com/kubernetes-incubator/service-catalog/pkg/apis/servicecatalog"
 )
 
-const servicePlanNameFmt string = `[-a-zA-Z0-9]+`
+const servicePlanNameFmt string = `[-.a-zA-Z0-9]+`
 const servicePlanNameMaxLength int = 63
 
 var servicePlanNameRegexp = regexp.MustCompile("^" + servicePlanNameFmt + "$")
diff --git a/pkg/apis/servicecatalog/validation/serviceplan_test.go b/pkg/apis/servicecatalog/validation/serviceplan_test.go
index 5cdd89f8186..5b38a1efe92 100644
--- a/pkg/apis/servicecatalog/validation/serviceplan_test.go
+++ b/pkg/apis/servicecatalog/validation/serviceplan_test.go
@@ -54,6 +54,15 @@ func TestValidateClusterServicePlan(t *testing.T) {
 			servicePlan: validClusterServicePlan(),
 			valid:       true,
 		},
+		{
+			name: "valid servicePlan - period in externalName",
+			servicePlan: func() *servicecatalog.ClusterServicePlan {
+				s := validClusterServicePlan()
+				s.Spec.ExternalName = "test.plan"
+				return s
+			}(),
+			valid: true,
+		},
 		{
 			name: "missing name",
 			servicePlan: func() *servicecatalog.ClusterServicePlan {