Control keys stipulate the type of activity and activity element.

You can use the control key to determine:

• Which business functions can be carried out for the activity, for example, whether costs can be calculated.
• How the activity is handled when processed, for example, whether it is costed or whether it can be confirmed.

You define the control key in Project System customizing. You can enter the defined control key in the network profile or standard network profile where it acts as a default value for new activities and activity elements. However, under certain conditions, you can change the control key in the detail screens for activities and activity elements.

This is useful if you discover that you cannot carry out an activity in your own organization (internally) because of capacity or time constraints, and want to have it performed externally.

You can change the following activity types using the control key:

• Internally processed activities into externally processed activities
• Externally processed activities into internally processed activities