While all other activities almost always reflect an OTX element, there is a Composite-activity OTX from several elements. Composite activities are a Abstraction layer on top of OTX represent and have to map the target user perspectives and terminologies. They are thus a measure for complexity reduction.

Eigenschaften-Dialog der Aktivitäten Composite ExecuteDiagServiceEx

In practice, any combination of OTX elements into a composite activity are summarized. Composite activities have their own specially designed to adjust the properties dialog, as shown above. An example of a composite activity is the ExceuteDiagServiceEx activity. The following table shows the sending of a diagnostic services in three different ways is shown. The composite activity ExceuteDiagServiceEx summarizes the linkage to an activity. Except for the meta-data, the composite activity is equivalent in terms of the OTX-illustrated Verkettung.