The business analyst describes the business process. In the purchasing example the description is fairly simple. The Buyer sends a purchase request to the Store. The Store then sends a credit check request to the Credit Agency. The Credit Agency either responds with a credit check ok message or a credit check failed message. Depending on which message is received, the Store will respond to the Buyer with a buy confirmed or a buy failed message.

The tasks in this phase are:

• Define the Participants
• Outline the Scenarios
• Create Message Examples