Message Flows

Message Flows are used to show the flow of messages between two participants that are able to send and receive them.

Pools, Activities and Events can be the source and target of message flows.

Message Flows connect to the Pool boundary or to flow objects within the Pool. You can’t use them to connect two flow elements within the same pool.

A Message Flow appears as a dashed line with an open circle at the start of the line and a clear arrowhead.

a Message Flow symbol

Message Flow attributes

Fill in this field in the Attributes tab:

  • Message Reference

    The ID of the Message that is sent or received by the Task.

    Click to view the list of message IDs and select an ID.


If you haven’t already defined the Message Definition at a global process level, you can define it in the Message tab:

  • Message

    The message that’s sent or received by a participant at the start, end or during or a process.

    • To add a message, click Add.

    • To remove a message, select the message from the list then click Remove.

    • To complete or edit a message, select the message from the list and fill in these fields:

      Field Description
      Name The name of the message.
      Description A description of the message.
      Item Definition The data type of the message.