A Message Map is used to pass data from one activity to another in the business process. Inputs define the data that the element requires to start the activity or process.

An input triggers an element to start, taking over from a preceding element which reached a stage of completion. The inputs also define the data that the element needs before it can start. During execution of a business process, the output of an activity in the business process becomes an input for the ensuing activity in the process.

Example of a Pre Assignment in the Message Map

A business process is modeled so that it returns the Product ID and the UnitsInStock. The product ID from this output message is used as an input (input message) for the next activity that retrieves information on the number of units in stock.


The product ID is the input for the process to start (input for the Start event). The product details are retrieved in the GetProduct activity, based on the product ID which was provided as an input to the Start event.

Drag the message (GetProductInput) from the Workspace Documents > Project pane on to the Start event.

A notification is sent to the Purchase Manager about the units in stock for the particular product. The output of the previous activity (GetProduct) forms an input for the Notify Application Service activity.

In the Pre Assignments (Notify Application Service activity), the output of the GetProduct activity is mapped to the input for the notify activity. The ProductID is mapped to the Header and the UnitsInStock is mapped to the XForm in the notify activity.