diff --git a/grpc-contrib/src/main/java/com/salesforce/grpc/contrib/interceptor/DefaultCallOptionsClientInterceptor.java b/grpc-contrib/src/main/java/com/salesforce/grpc/contrib/interceptor/DefaultCallOptionsClientInterceptor.java
new file mode 100644
index 00000000..c584e921
--- /dev/null
+++ b/grpc-contrib/src/main/java/com/salesforce/grpc/contrib/interceptor/DefaultCallOptionsClientInterceptor.java
@@ -0,0 +1,134 @@
+/*
+ *  Copyright (c) 2017, salesforce.com, inc.
+ *  All rights reserved.
+ *  Licensed under the BSD 3-Clause license.
+ *  For full license text, see LICENSE.txt file in the repo root  or https://opensource.org/licenses/BSD-3-Clause
+ */
+
+package com.salesforce.grpc.contrib.interceptor;
+
+import com.google.common.annotations.VisibleForTesting;
+import io.grpc.*;
+
+import java.lang.reflect.Field;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.function.BiFunction;
+import java.util.function.Function;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+/**
+ * {@code DefaultCallOptionsClientInterceptor} applies specified gRPC {@code CallOptions} to every outbound request.
+ * By default, {@code DefaultCallOptionsClientInterceptor} will not overwrite {@code CallOptions} already set on the
+ * outbound request.
+ *
+ * <p>Example uses include:
+ * <ul>
+ *     <li>Applying a set of {@code CallCredentials} to every request from any stub.</li>
+ *     <li>Applying a compression strategy to every request.</li>
+ *     <li>Attaching a custom {@code CallOptions.Key<T>} to every request.</li>
+ *     <li>Setting the {@code WaitForReady} bit on every request.</li>
+ *     <li>Preventing upstream users from tweaking {@code CallOptions} values by forcibly overwriting the value with a
+ *         specific default.</li>
+ * </ul>
+ */
+public class DefaultCallOptionsClientInterceptor implements ClientInterceptor {
+    private static final Field CUSTOM_OPTIONS_FIELD = getCustomOptionsField();
+
+    private static Field getCustomOptionsField() {
+        try {
+            Field f;
+            f = CallOptions.class.getDeclaredField("customOptions");
+            f.setAccessible(true);
+            return f;
+        } catch (NoSuchFieldException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    private CallOptions defaultOptions;
+    private boolean overwrite = false;
+
+    /**
+     * Constructs a {@code DefaultCallOptionsClientInterceptor}.
+     * @param options the set of {@code CallOptions} to apply to every call
+     */
+    public DefaultCallOptionsClientInterceptor(CallOptions options) {
+        this.defaultOptions = checkNotNull(options, "defaultOptions");
+    }
+
+    /**
+     * Instructs the interceptor to overwrite {@code CallOptions} values even if they are already present on the
+     * outbound request.
+     *
+     * @return this
+     */
+    public DefaultCallOptionsClientInterceptor overwriteExistingValues() {
+        this.overwrite = true;
+        return this;
+    }
+
+    public CallOptions getDefaultOptions() {
+        return defaultOptions;
+    }
+
+    public void setDefaultOptions(CallOptions options) {
+        this.defaultOptions = options;
+    }
+
+    @Override
+    public <ReqT, RespT> ClientCall<ReqT, RespT> interceptCall(MethodDescriptor<ReqT, RespT> method, CallOptions callOptions, Channel next) {
+        return next.newCall(method, patchOptions(callOptions));
+    }
+
+    @VisibleForTesting
+    CallOptions patchOptions(CallOptions baseOptions) {
+        CallOptions patchedOptions = baseOptions;
+
+        patchedOptions = patchOption(patchedOptions, CallOptions::getAuthority, CallOptions::withAuthority);
+        patchedOptions = patchOption(patchedOptions, CallOptions::getCredentials, CallOptions::withCallCredentials);
+        patchedOptions = patchOption(patchedOptions, CallOptions::getCompressor, CallOptions::withCompression);
+        patchedOptions = patchOption(patchedOptions, CallOptions::getDeadline, CallOptions::withDeadline);
+        patchedOptions = patchOption(patchedOptions, CallOptions::isWaitForReady, (callOptions, waitForReady) -> waitForReady ? callOptions.withWaitForReady() : callOptions.withoutWaitForReady());
+        patchedOptions = patchOption(patchedOptions, CallOptions::getMaxInboundMessageSize, CallOptions::withMaxInboundMessageSize);
+        patchedOptions = patchOption(patchedOptions, CallOptions::getMaxOutboundMessageSize, CallOptions::withMaxOutboundMessageSize);
+        patchedOptions = patchOption(patchedOptions, CallOptions::getExecutor, CallOptions::withExecutor);
+
+        for (ClientStreamTracer.Factory factory : defaultOptions.getStreamTracerFactories()) {
+            patchedOptions = patchedOptions.withStreamTracerFactory(factory);
+        }
+
+        for (CallOptions.Key<Object> key : customOptionKeys(defaultOptions)) {
+            patchedOptions = patchOption(patchedOptions, co -> co.getOption(key), (co, o) -> co.withOption(key, o));
+        }
+
+        return patchedOptions;
+    }
+
+    private <T> CallOptions patchOption(CallOptions baseOptions, Function<CallOptions, T> getter, BiFunction<CallOptions, T, CallOptions> setter) {
+        T baseValue = getter.apply(baseOptions);
+        if (baseValue == null || overwrite) {
+            T patchValue = getter.apply(defaultOptions);
+            if (patchValue != null) {
+                return setter.apply(baseOptions, patchValue);
+            }
+        }
+
+        return baseOptions;
+    }
+
+    @SuppressWarnings("unchecked")
+    private List<CallOptions.Key<Object>> customOptionKeys(CallOptions callOptions) {
+        try {
+            Object[][] customOptions = (Object[][]) CUSTOM_OPTIONS_FIELD.get(callOptions);
+            List<CallOptions.Key<Object>> keys = new ArrayList<>(customOptions.length);
+            for (Object[] arr : customOptions) {
+                keys.add((CallOptions.Key<Object>) arr[0]);
+            }
+            return keys;
+        } catch (IllegalAccessException e) {
+            throw new RuntimeException(e);
+        }
+    }
+}
diff --git a/grpc-contrib/src/test/java/com/salesforce/grpc/contrib/MoreMetadataTest.java b/grpc-contrib/src/test/java/com/salesforce/grpc/contrib/MoreMetadataTest.java
index 92eb5529..daa1edfe 100644
--- a/grpc-contrib/src/test/java/com/salesforce/grpc/contrib/MoreMetadataTest.java
+++ b/grpc-contrib/src/test/java/com/salesforce/grpc/contrib/MoreMetadataTest.java
@@ -68,6 +68,16 @@ public boolean equals(Object o) {
         }
     }
 
+    @Test
+    public void jsonMarshallerPrimitiveRoundtrip() {
+        Metadata.AsciiMarshaller<Integer> marshaller = MoreMetadata.JSON_MARSHALLER(Integer.class);
+        String s = marshaller.toAsciiString(42);
+        assertThat(s).isEqualTo("42");
+
+        Integer l = marshaller.parseAsciiString(s);
+        assertThat(l).isEqualTo(42);
+    }
+
     @Test
     public void protobufMarshallerRoundtrip() {
         HelloRequest request = HelloRequest.newBuilder().setName("World").build();
@@ -134,4 +144,18 @@ public void rawJsonToTypedJson() {
         assertThat(bar.cheese).isEqualTo("swiss");
         assertThat(bar.age).isEqualTo(42);
     }
+
+    @Test
+    public void rawBytesToTypedProto() {
+        Metadata.Key<byte[]> byteKey = Metadata.Key.of("key-bin", Metadata.BINARY_BYTE_MARSHALLER);
+        Metadata.Key<HelloRequest> protoKey = Metadata.Key.of("key-bin", MoreMetadata.PROTOBUF_MARSHALLER(HelloRequest.class));
+
+        HelloRequest request = HelloRequest.newBuilder().setName("World").build();
+        Metadata metadata = new Metadata();
+        metadata.put(byteKey, request.toByteArray());
+
+        HelloRequest request2 = metadata.get(protoKey);
+        assertThat(request2).isNotNull();
+        assertThat(request2.getName()).isEqualTo("World");
+    }
 }
diff --git a/grpc-contrib/src/test/java/com/salesforce/grpc/contrib/interceptor/DefaultCallOptionsClientInterceptorTest.java b/grpc-contrib/src/test/java/com/salesforce/grpc/contrib/interceptor/DefaultCallOptionsClientInterceptorTest.java
new file mode 100644
index 00000000..259e8f77
--- /dev/null
+++ b/grpc-contrib/src/test/java/com/salesforce/grpc/contrib/interceptor/DefaultCallOptionsClientInterceptorTest.java
@@ -0,0 +1,121 @@
+/*
+ *  Copyright (c) 2017, salesforce.com, inc.
+ *  All rights reserved.
+ *  Licensed under the BSD 3-Clause license.
+ *  For full license text, see LICENSE.txt file in the repo root  or https://opensource.org/licenses/BSD-3-Clause
+ */
+
+package com.salesforce.grpc.contrib.interceptor;
+
+import io.grpc.CallOptions;
+import io.grpc.ClientStreamTracer;
+import org.junit.Test;
+
+import static org.assertj.core.api.Java6Assertions.assertThat;
+
+public class DefaultCallOptionsClientInterceptorTest {
+    @Test
+    public void simpleValueTransfers() {
+        CallOptions baseOptions = CallOptions.DEFAULT;
+        CallOptions defaultOptions = CallOptions.DEFAULT.withAuthority("FOO");
+
+        DefaultCallOptionsClientInterceptor interceptor = new DefaultCallOptionsClientInterceptor(defaultOptions);
+
+        CallOptions patchedOptions = interceptor.patchOptions(baseOptions);
+
+        assertThat(patchedOptions.getAuthority()).isEqualTo("FOO");
+    }
+
+    @Test
+    public void clientStreamTracerTransfers() {
+        ClientStreamTracer.Factory factory1 = new ClientStreamTracer.Factory() {};
+        ClientStreamTracer.Factory factory2 = new ClientStreamTracer.Factory() {};
+
+        CallOptions baseOptions = CallOptions.DEFAULT.withStreamTracerFactory(factory1);
+        CallOptions defaultOptions = CallOptions.DEFAULT.withStreamTracerFactory(factory2);
+
+        DefaultCallOptionsClientInterceptor interceptor = new DefaultCallOptionsClientInterceptor(defaultOptions);
+
+        CallOptions patchedOptions = interceptor.patchOptions(baseOptions);
+
+        assertThat(patchedOptions.getStreamTracerFactories()).containsExactly(factory1, factory2);
+    }
+
+    @Test
+    public void customKeyTransfers() {
+        CallOptions.Key<String> k1 = CallOptions.Key.of("k1", null);
+        CallOptions.Key<String> k2 = CallOptions.Key.of("k2", null);
+
+        CallOptions baseOptions = CallOptions.DEFAULT.withOption(k1, "FOO");
+        CallOptions defaultOptions = CallOptions.DEFAULT.withOption(k2, "BAR");
+
+        DefaultCallOptionsClientInterceptor interceptor = new DefaultCallOptionsClientInterceptor(defaultOptions);
+
+        CallOptions patchedOptions = interceptor.patchOptions(baseOptions);
+
+        assertThat(patchedOptions.getOption(k1)).isEqualTo("FOO");
+        assertThat(patchedOptions.getOption(k2)).isEqualTo("BAR");
+    }
+
+    @Test
+    public void noOverwriteWorks() {
+        CallOptions baseOptions = CallOptions.DEFAULT.withAuthority("FOO");
+        CallOptions defaultOptions = CallOptions.DEFAULT.withAuthority("BAR");
+
+        DefaultCallOptionsClientInterceptor interceptor = new DefaultCallOptionsClientInterceptor(defaultOptions);
+
+        CallOptions patchedOptions = interceptor.patchOptions(baseOptions);
+
+        assertThat(patchedOptions.getAuthority()).isEqualTo("FOO");
+    }
+
+    @Test
+    public void noOverwriteWorksCustomKeys() {
+        CallOptions.Key<String> k1 = CallOptions.Key.of("k1", null);
+        CallOptions.Key<String> k2 = CallOptions.Key.of("k2", null);
+        CallOptions.Key<String> k3 = CallOptions.Key.of("k3", null);
+
+        CallOptions baseOptions = CallOptions.DEFAULT.withOption(k1, "FOO").withOption(k3, "BAZ");
+        CallOptions defaultOptions = CallOptions.DEFAULT.withOption(k2, "BAR").withOption(k3, "BOP");
+
+        DefaultCallOptionsClientInterceptor interceptor = new DefaultCallOptionsClientInterceptor(defaultOptions);
+
+        CallOptions patchedOptions = interceptor.patchOptions(baseOptions);
+
+        assertThat(patchedOptions.getOption(k1)).isEqualTo("FOO");
+        assertThat(patchedOptions.getOption(k2)).isEqualTo("BAR");
+        assertThat(patchedOptions.getOption(k3)).isEqualTo("BAZ");
+    }
+
+    @Test
+    public void overwriteWorks() {
+        CallOptions baseOptions = CallOptions.DEFAULT.withAuthority("FOO");
+        CallOptions defaultOptions = CallOptions.DEFAULT.withAuthority("BAR");
+
+        DefaultCallOptionsClientInterceptor interceptor = new DefaultCallOptionsClientInterceptor(defaultOptions)
+                .overwriteExistingValues();
+
+        CallOptions patchedOptions = interceptor.patchOptions(baseOptions);
+
+        assertThat(patchedOptions.getAuthority()).isEqualTo("BAR");
+    }
+
+    @Test
+    public void overwriteWorksCustomKeys() {
+        CallOptions.Key<String> k1 = CallOptions.Key.of("k1", null);
+        CallOptions.Key<String> k2 = CallOptions.Key.of("k2", null);
+        CallOptions.Key<String> k3 = CallOptions.Key.of("k3", null);
+
+        CallOptions baseOptions = CallOptions.DEFAULT.withOption(k1, "FOO").withOption(k3, "BAZ");
+        CallOptions defaultOptions = CallOptions.DEFAULT.withOption(k2, "BAR").withOption(k3, "BOP");
+
+        DefaultCallOptionsClientInterceptor interceptor = new DefaultCallOptionsClientInterceptor(defaultOptions)
+                .overwriteExistingValues();
+
+        CallOptions patchedOptions = interceptor.patchOptions(baseOptions);
+
+        assertThat(patchedOptions.getOption(k1)).isEqualTo("FOO");
+        assertThat(patchedOptions.getOption(k2)).isEqualTo("BAR");
+        assertThat(patchedOptions.getOption(k3)).isEqualTo("BOP");
+    }
+}