Classes Member Classes You can have a member property of your class that has a type that is of another class and it will be serialized as well as long as it inherits from IMessageSerializable. The definition of this member class should follow all the same rules that you would follow for the parent class. Inherited Classes If your class inherits from another class, the properties of the class you inherit from will be included in your message Serialization/Deserialization as long as the class being inherited from derives from IMessageSerializable. By default, the properties from the class being inherited from will be serialized/deserialized first (i.e. they will be considered the first fields of the message). However you can set the PutInheritedPropertiesLast property of the MessageClass attribute to true to indicate that the inherited properties should actually go at the end of the message.