Index: firmware/App/Services/SystemCommMessages.c
===================================================================
diff -u -rb6b733b8d1f25bc2dbe2a94c620cd80aa3ae06f7 -r401c4027b0e59182771f0c620465b34579f203f5
--- firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision b6b733b8d1f25bc2dbe2a94c620cd80aa3ae06f7)
+++ firmware/App/Services/SystemCommMessages.c	(.../SystemCommMessages.c)	(revision 401c4027b0e59182771f0c620465b34579f203f5)
@@ -30,6 +30,7 @@
 #include "ModeTreatmentParams.h"
 #include "PresOccl.h"
 #include "RTC.h"
+#include "SampleWater.h"
 #include "SafetyShutdown.h"
 #include "SystemComm.h"
 #include "SystemCommMessages.h"
@@ -471,8 +472,64 @@
     result = serializeMessage( msg, COMM_BUFFER_OUT_CAN_HD_2_UI, ACK_REQUIRED );
 
     return result;
-}
+}
 
+/*********************************************************************//**
+ * @brief
+ * The handleSampleWaterCmd function handles a sample water user action command
+ * message from the UI.
+ * @details Inputs: none
+ * @details Outputs: message handled
+ * @param message a pointer to the message to handle
+ * @return none.
+ *************************************************************************/
+void handleSampleWaterCmd( MESSAGE_T *message )
+{
+    if ( sizeof( U32 ) == message->hdr.payloadLen )
+    {
+        U32 cmd;
+
+        memcpy( &cmd, &message->payload[0], sizeof( U32 ) );
+
+        signalSampleWaterUserAction( (REQUESTED_SAMPLE_WATER_USER_ACTIONS_T)cmd );
+    }
+    else
+    {
+        sendAckResponseMsg( (MSG_ID_T)message->hdr.msgID, COMM_BUFFER_OUT_CAN_HD_2_UI, FALSE );
+    }
+}
+
+/*********************************************************************//**
+ * @brief
+ * The sendSampleWaterCmdResponse function constructs a sample water user action
+ * response to the UI and queues the msg for transmit on the appropriate CAN channel.
+ * @details Inputs: none
+ * @details Outputs: Sample water command response msg constructed and queued.
+ * @param accepted T/F - was sample water request accepted?
+ * @param rejReason reason why request was rejected (or zero if accepted)
+ * @return TRUE if msg successfully queued for transmit, FALSE if not
+ *************************************************************************/
+BOOL sendSampleWaterCmdResponse( BOOL accepted, U32 rejReason )
+{
+    BOOL result;
+    MESSAGE_T msg;
+    U08 *payloadPtr = msg.payload;
+
+    // Create a message record
+    blankMessage( &msg );
+    msg.hdr.msgID = MSG_ID_HD_SAMPLE_WATER_CMD_RESPONSE;
+    msg.hdr.payloadLen = sizeof( BOOL ) + sizeof( U32 );
+
+    memcpy( payloadPtr, &accepted, sizeof( BOOL ) );
+    payloadPtr += sizeof( BOOL );
+    memcpy( payloadPtr, &rejReason, sizeof( U32 ) );
+
+    // Serialize the message (w/ sync, CRC, and appropriate CAN padding) and add serialized message data to appropriate comm buffer
+    result = serializeMessage( msg, COMM_BUFFER_OUT_CAN_HD_2_UI, ACK_REQUIRED );
+
+    return result;
+}
+
 /*********************************************************************//**
  * @brief
  * The sendDialysateTempTargetsToDG function constructs a dialysate temperature