The Unified Method Framework (UMF) defines some constraints with regards to the definition and use of standard categories. Those constraints vary for the different standard category types.

The UMF implements a Delayed Assignment approach for disciplines, domains and work product kinds. It does not implement a delayed category assignment for role sets because the definition of roles and role sets are strongly linked. Roles are assigned to role sets in the same plug-in as where the roles are defined, the Role Definition plug-in (their definitions are shared). For more information on roles in the UMF, see Guideline: Roles in the UMF. The UMF also does not implement a delayed category assignment for tools because the assignment of tool mentors to tools does not change (tool mentors are written for a specific tool). For more information on tools in the UMF, see Guideline: Tool Information in the UMF.

The "delayed standard categories" (disciplines, domains and work product kinds) are defined in a Category Definition Base plug-in. Elements are assigned to these categories in the Assign plug-ins associated with the Base plug-in that contains the elements to be assigned (tasks and work products). For information on how these assignments are defined, see Guideline: Delayed Assignment in the UMF. 

The benefits to the UMF approach to standard categories are:

• The same categories can be used with different element assignments (shared Category Definition plug-ins)
• Alternate category definitions and element assignments can be defined (provide alternate Category Definition and Assign plug-ins)

For more information on Category Definition plug-ins, Role Definition plug-ins and Tool Definition plug-ins, see Concept: Practice Library Plug-In Types. For more information on Base and Assign plug-ins, see Concept: Practice Library Plug-In Parts. 

For an example of a Category Definition Base plug-in, see UMF Category Definition Base Plug-In Example.