The first step is to create the example messages, to be used by the scenarios that will document the business requirements.

Some previously defined examples can be found in the purchasing Eclipse project. For example, the Buy request is defined as:

<tns:BuyRequest xmlns:tns="http://www.jboss.org/examples/store"
            id="1" product="Laptop" />

Although a schema may not have been defined at this stage, unless one previously existed that is being reused, it is a good idea to define a namespace for the message type. This is because it will be used within the scenarios and architectural models defined in the following stage. If the namespace was not specified at this stage, then the example messages, scenarios and architectural models would need to be updated at a later stage.

Although this phase has been defined before the definition of the scenarios, in practice these phases are iterative. So scenarios and example messages would be defined concurrently, as the requirements evolve through discussions between the business analyst and users.