A Unit Of Behavior (UOB) is a distinguishable packet of information about an event, decision, act, or process. Modelers describe UOBs with elaboration documents, child diagrams, or decompositions.

Consisting of a set of participating objects and their relations, Elaboration Documents define real-world UOBs. An Elaboration Document identifies a UOBs facts and constraints and gives it a textual description. Every UOB has an Elaboration Document associated with it.

You can create child IDEF3 process flow diagrams to graphically show process details of a UOB.

If you have automatic numbering turned on (click Tools, Preferences, Number), UOBs are automatically numbered as you draw them, according to the rules of IDEF3. You can also manually number a UOB by opening the UOB definition dialog box, and placing a number in the Number property on the Symbol tab.

You can define the following properties on the main tab of the UOB definition.

In IDEF3 terminology, you provide an elaboration to a UOB – this is its principal definition. The elaboration consists of a description of the UOB in terms of its set of participating objects and their relations. In System Architect, the UOB's definition dialog provides an Elaboration tab, that enables you to list and define the UOB's associated objects, facts, and constraints.

This is a business object that is needed or occurs because of this UOB. Within the object's definition, you can specify its type and general information in the Glossary Text field. You might want to later transform IDEF3 business objects to UML classes using System Architect automation (VBA macros).

Facts are assertions made about objects; they are relationships that hold true in the real world. You can optionally describe the fact in its Description property.

Most generally, a statement which must (or equivalently, must not) hold in a system. Most often, constraints express logical properties of, or connections between, domain objects that must be maintained if the system is to function as intended. Constraints are distinguished conditions known to hold between the objects in a process or between the processes themselves.

You can specify Project Data of a UOB.

You can define project data in the Project Planning tab of the UOB definition dialog:

The duration time of the project. Units of measure are selected in Time Measure .

The unit with which you will measure the duration of the project.

Toggle on whether or not the project time is fixed.

Enter the cost budgeted for the project.

Enter the fixed cost of the project, if there is one.

Enter the actual cost of the project.

Toggle on whether or not this function/activity is a milestone.

Toggle on whether or not this function/activity is a summary task.

Toggle on whether or not this function/activity is a priority in the project.

Enter a Work Breakdown Structure Code if there is one.