When you decompose a single function on an IDEF0 diagram with a child IDEF0 diagram, you model the major subfunctions on the child diagram. To show increasing detail, you can create child diagrams for the subfunctions on the child diagram, and so on. You should keep the overall scope of each child diagram within the scope of the parent Function/Activity symbol in IDEF0 at all times.

To create an IDEF0 Constraint (or Decomposition) diagram, see Creating IDEF0 decomposition diagrams.

When decomposing a Function/Activity with another IDEF0 diagram, you must be concerned with the following: