diff --git a/metrics-server/pkg/sink/interfaces.go b/metrics-server/pkg/sink/interfaces.go
new file mode 100644
index 0000000..a8faf68
--- /dev/null
+++ b/metrics-server/pkg/sink/interfaces.go
@@ -0,0 +1,25 @@
+// Copyright 2018 The Kubernetes Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package sink
+
+import (
+	"github.com/kubernetes-incubator/metrics-server/pkg/sources"
+)
+
+// MetricSink knows how to receive metrics batches from a source.
+type MetricSink interface {
+	// Receive ingests a new batch of metrics.
+	Receive(*sources.MetricsBatch) error
+}