diff --git a/src/main/java/net/openhft/chronicle/hash/serialization/impl/BytesMarshallableDataAccess.java b/src/main/java/net/openhft/chronicle/hash/serialization/impl/BytesMarshallableDataAccess.java
index 7ca8fc7c4..8443f3046 100644
--- a/src/main/java/net/openhft/chronicle/hash/serialization/impl/BytesMarshallableDataAccess.java
+++ b/src/main/java/net/openhft/chronicle/hash/serialization/impl/BytesMarshallableDataAccess.java
@@ -16,9 +16,7 @@
 
 package net.openhft.chronicle.hash.serialization.impl;
 
-import net.openhft.chronicle.bytes.Bytes;
-import net.openhft.chronicle.bytes.BytesMarshallable;
-import net.openhft.chronicle.bytes.RandomDataInput;
+import net.openhft.chronicle.bytes.*;
 import net.openhft.chronicle.hash.Data;
 import net.openhft.chronicle.hash.serialization.DataAccess;
 import net.openhft.chronicle.wire.WireIn;
@@ -28,8 +26,10 @@ import org.jetbrains.annotations.Nullable;
 public class BytesMarshallableDataAccess<T extends BytesMarshallable>
         extends InstanceCreatingMarshaller<T> implements DataAccess<T>, Data<T> {
 
-    /** Cache field */
+    // Cache fields
+    private transient boolean bytesInit;
     private transient Bytes bytes;
+    private transient VanillaBytes targetBytes;
 
     /** State field */
     private transient T instance;
@@ -47,13 +47,23 @@ public class BytesMarshallableDataAccess<T extends BytesMarshallable>
 
     private void initTransients() {
         bytes = Bytes.allocateElasticDirect(1);
+        targetBytes = VanillaBytes.vanillaBytes();
     }
 
     @Override
     public RandomDataInput bytes() {
+        initBytes();
         return bytes.bytesStore();
     }
 
+    private void initBytes() {
+        if (!bytesInit) {
+            bytes.clear();
+            instance.writeMarshallable(bytes);
+            bytesInit = true;
+        }
+    }
+
     @Override
     public long offset() {
         return 0;
@@ -61,9 +71,23 @@ public class BytesMarshallableDataAccess<T extends BytesMarshallable>
 
     @Override
     public long size() {
+        initBytes();
         return bytes.readRemaining();
     }
 
+    @Override
+    public void writeTo(RandomDataOutput target, long targetOffset) {
+        if (bytesInit) {
+            target.write(targetOffset, bytes(), offset(), size());
+        } else {
+            targetBytes.bytesStore((BytesStore) target, targetOffset,
+                    target.capacity() - targetOffset);
+            targetBytes.writePosition(targetOffset);
+            instance.writeMarshallable(targetBytes);
+            targetBytes.bytesStore(NoBytesStore.NO_BYTES_STORE, 0, 0);
+        }
+    }
+
     @Override
     public T get() {
         return instance;
@@ -73,6 +97,7 @@ public class BytesMarshallableDataAccess<T extends BytesMarshallable>
     public T getUsing(@Nullable T using) {
         if (using == null)
             using = createInstance();
+        initBytes();
         using.readMarshallable(bytes);
         bytes.readPosition(0);
         return using;
@@ -96,8 +121,7 @@ public class BytesMarshallableDataAccess<T extends BytesMarshallable>
     @Override
     public Data<T> getData(@NotNull T instance) {
         this.instance = instance;
-        bytes.clear();
-        instance.writeMarshallable(bytes);
+        bytesInit = false;
         return this;
     }
 
diff --git a/src/test/java/net/openhft/chronicle/map/BytesMarshallableValueTest.java b/src/test/java/net/openhft/chronicle/map/BytesMarshallableValueTest.java
new file mode 100644
index 000000000..48da84689
--- /dev/null
+++ b/src/test/java/net/openhft/chronicle/map/BytesMarshallableValueTest.java
@@ -0,0 +1,64 @@
+/*
+ *      Copyright (C) 2015  higherfrequencytrading.com
+ *
+ *      This program is free software: you can redistribute it and/or modify
+ *      it under the terms of the GNU Lesser General Public License as published by
+ *      the Free Software Foundation, either version 3 of the License.
+ *
+ *      This program is distributed in the hope that it will be useful,
+ *      but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *      GNU Lesser General Public License for more details.
+ *
+ *      You should have received a copy of the GNU Lesser General Public License
+ *      along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package net.openhft.chronicle.map;
+
+import net.openhft.chronicle.bytes.Bytes;
+import net.openhft.chronicle.bytes.BytesMarshallable;
+import org.junit.Assert;
+import org.junit.Test;
+
+public class BytesMarshallableValueTest {
+
+    @Test
+    public void bytesMarshallableValueTest() {
+        try (ChronicleMap<Integer, Value> map = ChronicleMap
+                .of(Integer.class, Value.class)
+                .averageValue(new Value(1, "foo"))
+                .entries(10)
+                .create()) {
+            map.put(1, new Value(1, "bar"));
+            Assert.assertEquals("bar", map.replace(1, new Value(2, "baz")).foo);
+            map.remove(1);
+        }
+    }
+
+    public static class Value implements BytesMarshallable {
+
+        int x;
+        String foo;
+
+        public Value(int x, String foo) {
+            this.x = x;
+            this.foo = foo;
+        }
+
+        public Value() {
+        }
+
+        @Override
+        public void readMarshallable(Bytes<?> bytes) {
+            x = bytes.readInt();
+            foo = bytes.readUtf8();
+        }
+
+        @Override
+        public void writeMarshallable(Bytes bytes) {
+            bytes.writeInt(x);
+            bytes.writeUtf8(foo);
+        }
+    }
+}