diff --git a/applications/message_handler/test/message_client.cpp b/applications/message_handler/test/message_client.cpp
new file mode 100644
index 0000000..4209564
--- /dev/null
+++ b/applications/message_handler/test/message_client.cpp
@@ -0,0 +1,91 @@
+/*
+ * Copyright (c) 2022 Arm Limited.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * 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
+ *
+ * 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.
+ */
+
+#include "FreeRTOS.h"
+#include "task.h"
+
+#include "ethosu_core_interface.h"
+#include "message_client.hpp"
+
+using namespace EthosU;
+
+namespace MessageHandler {
+
+MessageClient::MessageClient(EthosU::ethosu_core_queue &_inputMessageQueue,
+                             EthosU::ethosu_core_queue &_outputMessageQueue,
+                             Mailbox::Mailbox &_mailbox) :
+    input(_inputMessageQueue),
+    output(_outputMessageQueue), mailbox(_mailbox) {}
+
+bool MessageClient::sendInputMessage(const uint32_t type, const void *src, uint32_t length) {
+    if (!input.write(type, src, length)) {
+        printf("ERROR: Msg: Failed to write ping request. No mailbox message sent\n");
+        return false;
+    }
+
+    mailbox.sendMessage();
+    mailbox.handleMessage();
+    return true;
+}
+
+bool MessageClient::waitAndReadOutputMessage(const uint32_t expected_type, uint8_t *dst, uint32_t length) {
+    constexpr TickType_t delay    = pdMS_TO_TICKS(2);
+    constexpr TickType_t deadline = pdMS_TO_TICKS(/* 1 minute */ 60 * 1000 * 1000);
+    struct ethosu_core_msg msg;
+
+    TickType_t totalDelay = 0;
+    while (output.available() == 0) {
+        vTaskDelay(delay);
+        totalDelay += delay;
+        if (totalDelay >= deadline) {
+            return false;
+        }
+    }
+
+    if (!output.read(msg)) {
+        printf("ERROR: Failed to read msg header\n");
+        return false;
+    }
+
+    if (msg.magic != ETHOSU_CORE_MSG_MAGIC) {
+        printf("ERROR: Invalid Magic\n");
+        return false;
+    }
+
+    if (msg.type != expected_type) {
+        printf("ERROR: Wrong message type\n");
+        return false;
+    }
+
+    if (msg.length != length) {
+        printf("ERROR: Wrong message size\n");
+        return false;
+    }
+
+    if (length == 0) {
+        return true;
+    }
+
+    if (!output.read(dst, length)) {
+        printf("ERROR: Failed to read msg payload\n");
+        return false;
+    }
+
+    return true;
+}
+} // namespace MessageHandler