diff --git a/pkg/master/import_known_versions_test.go b/pkg/master/import_known_versions_test.go
index e3b977c8dc0..592b35ffdfe 100644
--- a/pkg/master/import_known_versions_test.go
+++ b/pkg/master/import_known_versions_test.go
@@ -17,10 +17,18 @@ limitations under the License.
 package master
 
 import (
+	"encoding/json"
+	"reflect"
 	"strings"
 	"testing"
 
+	"k8s.io/kubernetes/pkg/api"
+	"k8s.io/kubernetes/pkg/api/v1"
 	"k8s.io/kubernetes/pkg/apimachinery/registered"
+	metav1 "k8s.io/kubernetes/pkg/apis/meta/v1"
+	"k8s.io/kubernetes/pkg/runtime"
+	"k8s.io/kubernetes/pkg/runtime/schema"
+	"k8s.io/kubernetes/pkg/util/intstr"
 	"k8s.io/kubernetes/pkg/util/sets"
 )
 
@@ -49,3 +57,123 @@ func TestGroupVersions(t *testing.T) {
 		}
 	}
 }
+
+func TestTypeTags(t *testing.T) {
+	for gvk, knownType := range api.Scheme.AllKnownTypes() {
+		if gvk.Version == runtime.APIVersionInternal {
+			ensureNoTags(t, gvk, knownType, nil)
+		} else {
+			ensureTags(t, gvk, knownType, nil)
+		}
+	}
+}
+
+// These types are registered in external versions, and therefore include json tags,
+// but are also registered in internal versions (or referenced from internal types),
+// so we explicitly allow tags for them
+var typesAllowedTags = map[reflect.Type]bool{
+	reflect.TypeOf(intstr.IntOrString{}):    true,
+	reflect.TypeOf(metav1.Time{}):           true,
+	reflect.TypeOf(metav1.Duration{}):       true,
+	reflect.TypeOf(metav1.TypeMeta{}):       true,
+	reflect.TypeOf(metav1.ListMeta{}):       true,
+	reflect.TypeOf(metav1.OwnerReference{}): true,
+	reflect.TypeOf(metav1.LabelSelector{}):  true,
+	reflect.TypeOf(metav1.GetOptions{}):     true,
+	reflect.TypeOf(metav1.ExportOptions{}):  true,
+}
+
+func ensureNoTags(t *testing.T, gvk schema.GroupVersionKind, tp reflect.Type, parents []reflect.Type) {
+	if _, ok := typesAllowedTags[tp]; ok {
+		return
+	}
+
+	parents = append(parents, tp)
+
+	switch tp.Kind() {
+	case reflect.Map, reflect.Slice, reflect.Ptr:
+		ensureNoTags(t, gvk, tp.Elem(), parents)
+
+	case reflect.String, reflect.Bool, reflect.Float32, reflect.Int, reflect.Int32, reflect.Int64, reflect.Uint8, reflect.Uintptr, reflect.Uint32, reflect.Uint64, reflect.Interface:
+		// no-op
+
+	case reflect.Struct:
+		for i := 0; i < tp.NumField(); i++ {
+			f := tp.Field(i)
+			jsonTag := f.Tag.Get("json")
+			protoTag := f.Tag.Get("protobuf")
+			if len(jsonTag) > 0 || len(protoTag) > 0 {
+				t.Errorf("Internal types should not have json or protobuf tags. %#v has tag on field %v: %v", gvk, f.Name, f.Tag)
+				for i, tp := range parents {
+					t.Logf("%s%v:", strings.Repeat("  ", i), tp)
+				}
+			}
+
+			ensureNoTags(t, gvk, f.Type, parents)
+		}
+
+	default:
+		t.Errorf("Unexpected type %v in %#v", tp.Kind(), gvk)
+		for i, tp := range parents {
+			t.Logf("%s%v:", strings.Repeat("  ", i), tp)
+		}
+	}
+}
+
+var (
+	marshalerType   = reflect.TypeOf((*json.Marshaler)(nil)).Elem()
+	unmarshalerType = reflect.TypeOf((*json.Unmarshaler)(nil)).Elem()
+)
+
+// These fields are limited exceptions to the standard JSON naming structure.
+// Additions should only be made if a non-standard field name was released and cannot be changed for compatibility reasons.
+var allowedNonstandardJSONNames = map[reflect.Type]string{
+	reflect.TypeOf(v1.DaemonEndpoint{}): "Port",
+}
+
+func ensureTags(t *testing.T, gvk schema.GroupVersionKind, tp reflect.Type, parents []reflect.Type) {
+	// This type handles its own encoding/decoding and doesn't need json tags
+	if tp.Implements(marshalerType) && (tp.Implements(unmarshalerType) || reflect.PtrTo(tp).Implements(unmarshalerType)) {
+		return
+	}
+
+	parents = append(parents, tp)
+
+	switch tp.Kind() {
+	case reflect.Map, reflect.Slice, reflect.Ptr:
+		ensureTags(t, gvk, tp.Elem(), parents)
+
+	case reflect.String, reflect.Bool, reflect.Float32, reflect.Int, reflect.Int32, reflect.Int64, reflect.Uint8, reflect.Uintptr, reflect.Uint32, reflect.Uint64, reflect.Interface:
+		// no-op
+
+	case reflect.Struct:
+		for i := 0; i < tp.NumField(); i++ {
+			f := tp.Field(i)
+			jsonTag := f.Tag.Get("json")
+			if len(jsonTag) == 0 {
+				t.Errorf("External types should have json tags. %#v tags on field %v are: %s", gvk, f.Name, f.Tag)
+				for i, tp := range parents {
+					t.Logf("%s%v", strings.Repeat("  ", i), tp)
+				}
+			}
+
+			jsonTagName := strings.Split(jsonTag, ",")[0]
+			if len(jsonTagName) > 0 && (jsonTagName[0] < 'a' || jsonTagName[0] > 'z') && jsonTagName != "-" && allowedNonstandardJSONNames[tp] != jsonTagName {
+				t.Errorf("External types should have json names starting with lowercase letter. %#v has json tag on field %v with name %s", gvk, f.Name, jsonTagName)
+				t.Log(tp)
+				t.Log(allowedNonstandardJSONNames[tp])
+				for i, tp := range parents {
+					t.Logf("%s%v", strings.Repeat("  ", i), tp)
+				}
+			}
+
+			ensureTags(t, gvk, f.Type, parents)
+		}
+
+	default:
+		t.Errorf("Unexpected type %v in %#v", tp.Kind(), gvk)
+		for i, tp := range parents {
+			t.Logf("%s%v:", strings.Repeat("  ", i), tp)
+		}
+	}
+}