The As-Is Application Landscape main purpose is to provide insight in the internal and external application systems that enable information provision. The models describing the Application Landscape are the Application Model, the Application Interface Model and the Transaction Model. Depending on what has been decided on the scope of the BA engagement in Focus and Direction, one, two or all three models may be created. The depth and level of detail may also have been indicated or can be derived from what has been agreed on the scope of the engagement. Also the client may have provided complete or partial models as described in the previous task.

The Application Model consists of application diagrams and accompanying text that explains how information services are provided through an application or application suite. The basic function of the Application Model is therefore a description of the functionality that applications provide or more likely the functionality that a set of applications provide. E.g. an application model may show that a customer ordering function is provided by application X.

The Interface Model is illustrated by an application diagram that focuses on how applications interface one to another and interface to external systems. Each interface is described separately in textual form.

The Transaction Model is described using Sequence Diagrams that illustrate the dynamics of the application suite under consideration. A Sequence Diagram shows how business transactions are handled in a number of steps and flow through various systems - internal and external -- and possibly manual processes.

Depending on the specific engagement an Application Model can be large and complex involving many IT systems both in and outside the scope of the engagement or it may be small and simple.