diff --git a/src/main/java/seng302/server/messages/BoatLocationMessage.java b/src/main/java/seng302/server/messages/BoatLocationMessage.java
index a475128b..4b914699 100644
--- a/src/main/java/seng302/server/messages/BoatLocationMessage.java
+++ b/src/main/java/seng302/server/messages/BoatLocationMessage.java
@@ -65,11 +65,66 @@ public class BoatLocationMessage extends Message {
         setHeader(new Header(MessageType.BOAT_LOCATION, 1, (short) getSize()));
     }
 
+    /**
+     * Convert binary latitude or longitude to floating point number
+     * @param binaryPackedLatLon Binary packed lat OR lon
+     * @return Floating point lat/lon
+     */
+    public static double binaryPackedToLatLon(long binaryPackedLatLon){
+        return (double)binaryPackedLatLon * 180.0 / 2147483648.0;
+    }
+
+    /**
+     * Convert binary packed heading to floating point number
+     * @param binaryPackedHeading Binary packed heading
+     * @return heading as a decimal
+     */
+    public static double binaryPackedHeadingToDouble(long binaryPackedHeading){
+        return (double)binaryPackedHeading * 360.0 / 65536.0;
+    }
+
+    /**
+     * Convert binary packed wind angle to floating point number
+     * @param binaryPackedWindAngle Binary packed wind angle
+     * @return wind angle as a decimal
+     */
+    public static double binaryPackedWindAngleToDouble(long binaryPackedWindAngle){
+        return (double)binaryPackedWindAngle*180.0/32768.0;
+    }
+
+    /**
+     * Convert a latitude or longitude to a binary packed long
+     * @param latLon A floating point latitude/longitude
+     * @return A binary packed lat/lon
+     */
+    public static long latLonToBinaryPackedLong(double latLon){
+        return (long)((536870912 * latLon) / 45);
+    }
+
+    /**
+     * Convert a heading to a binary packed long
+     * @param heading A floating point heading
+     * @return A binary packed heading
+     */
+    public static long headingToBinaryPackedLong(double heading){
+        return (long)((8192*heading)/45);
+    }
+
+    /**
+     * Convert a wind angle to a binary packed long
+     * @param windAngle Floating point wind angle
+     * @return A binary packed wind angle
+     */
+    public static long windAngleToBinaryPackedLong(double windAngle){
+        return (long)((8192*windAngle)/45);
+    }
+
     @Override
     public int getSize() {
-        return 56;
+        return MESSAGE_SIZE;
     }
 
+
     @Override
     public void send(DataOutputStream outputStream) {
         allocateBuffer();
diff --git a/src/main/java/seng302/server/messages/MarkRoundingMessage.java b/src/main/java/seng302/server/messages/MarkRoundingMessage.java
new file mode 100644
index 00000000..405c46ff
--- /dev/null
+++ b/src/main/java/seng302/server/messages/MarkRoundingMessage.java
@@ -0,0 +1,62 @@
+package seng302.server.messages;
+
+import java.io.DataOutputStream;
+import java.io.IOException;
+
+public class MarkRoundingMessage extends Message{
+    private final long MESSAGE_VERSION_NUMBER = 1;
+    private final int MESSAGE_SIZE = 21;
+
+    private long time;
+    private long ackNumber;
+    private long raceId;
+    private long sourceId;
+    private RoundingBoatStatus boatStatus;
+    private RoundingSide roundingSide;
+    private long markId;
+
+    /**
+     * This message is sent when a boat passes a mark, start line, or finish line
+     * The purpose of this is to record the time when yachts cross marks
+     */
+    public MarkRoundingMessage(int ackNumber, int raceId, int sourceId, RoundingBoatStatus roundingBoatStatus,
+                               RoundingSide roundingSide, int markId){
+        this.time = System.currentTimeMillis() / 1000L;
+        this.ackNumber = ackNumber;
+        this.raceId = raceId;
+        this.sourceId = sourceId;
+        this.boatStatus = roundingBoatStatus;
+        this.roundingSide = roundingSide;
+        this.markId = markId;
+
+        setHeader(new Header(MessageType.MARK_ROUNDING, 1, (short) getSize()));
+    }
+
+    @Override
+    public int getSize() {
+        return MESSAGE_SIZE;
+    }
+
+    @Override
+    public void send(DataOutputStream outputStream) {
+        allocateBuffer();
+        writeHeaderToBuffer();
+
+        putByte((byte) MESSAGE_VERSION_NUMBER);
+        putInt((int) time, 6);
+        putInt((int) ackNumber, 2);
+        putInt((int) raceId, 4);
+        putInt((int) sourceId, 4);
+        putByte((byte) boatStatus.getCode());
+        putByte((byte) roundingSide.getCode());
+        putByte((byte) markId);
+
+        writeCRC();
+
+        try {
+            outputStream.write(getBuffer().array());
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+}
diff --git a/src/main/java/seng302/server/messages/MarkType.java b/src/main/java/seng302/server/messages/MarkType.java
new file mode 100644
index 00000000..abbacc6f
--- /dev/null
+++ b/src/main/java/seng302/server/messages/MarkType.java
@@ -0,0 +1,20 @@
+package seng302.server.messages;
+
+/**
+ * Types of marks boats can round
+ */
+public enum MarkType {
+    UNKNOWN(0),
+    ROUNDING_MARK(1),
+    GATE(2);
+
+    private long code;
+
+    MarkType(long code) {
+        this.code = code;
+    }
+
+    public long getCode(){
+        return code;
+    }
+}
diff --git a/src/main/java/seng302/server/messages/RoundingBoatStatus.java b/src/main/java/seng302/server/messages/RoundingBoatStatus.java
new file mode 100644
index 00000000..32eb2447
--- /dev/null
+++ b/src/main/java/seng302/server/messages/RoundingBoatStatus.java
@@ -0,0 +1,21 @@
+package seng302.server.messages;
+
+/**
+ * The status of a boat rounding a mark
+ */
+public enum RoundingBoatStatus {
+    UNKNOWN(0),
+    RACING(1),
+    DSQ(2),
+    WITHDRAWN(3);
+
+    private long code;
+
+    RoundingBoatStatus(long code) {
+        this.code = code;
+    }
+
+    public long getCode(){
+        return code;
+    }
+}
diff --git a/src/main/java/seng302/server/messages/RoundingSide.java b/src/main/java/seng302/server/messages/RoundingSide.java
new file mode 100644
index 00000000..5cc4097c
--- /dev/null
+++ b/src/main/java/seng302/server/messages/RoundingSide.java
@@ -0,0 +1,20 @@
+package seng302.server.messages;
+
+/**
+ * The side the boat rounded the mark
+ */
+public enum RoundingSide {
+    UNKNOWN(0),
+    PORT(1),
+    STARBOARD(2);
+
+    private long code;
+
+    RoundingSide(long code) {
+        this.code = code;
+    }
+
+    public long getCode(){
+        return code;
+    }
+}
diff --git a/src/test/java/seng302/server/TestConversions.java b/src/test/java/seng302/server/TestConversions.java
new file mode 100644
index 00000000..91bf44b3
--- /dev/null
+++ b/src/test/java/seng302/server/TestConversions.java
@@ -0,0 +1,35 @@
+package seng302.server;
+
+import org.junit.Test;
+import seng302.server.messages.BoatLocationMessage;
+
+import static junit.framework.TestCase.assertEquals;
+
+/**
+ * Test conversions used by the boat location messages
+ */
+public class TestConversions {
+    @Test
+    public void testLatLonConversion(){
+        long binaryPacked = BoatLocationMessage.latLonToBinaryPackedLong(3232.323);
+        double original = BoatLocationMessage.binaryPackedToLatLon(binaryPacked);
+
+        assertEquals(3232.323, original, 0.01);
+    }
+
+    @Test
+    public void testWindAngleConversion(){
+        long binaryPacked = BoatLocationMessage.windAngleToBinaryPackedLong(3232.323);
+        double original = BoatLocationMessage.binaryPackedWindAngleToDouble(binaryPacked);
+
+        assertEquals(3232.323, original, 0.01);
+    }
+
+    @Test
+    public void testHeadingConversion(){
+        long binaryPacked = BoatLocationMessage.headingToBinaryPackedLong(3232.323);
+        double original = BoatLocationMessage.binaryPackedHeadingToDouble(binaryPacked);
+
+        assertEquals(3232.323, original, 0.01);
+    }
+}