What?
"A supporting process workflow whose purpose is to identify, define, and baseline items; control modifications and releases of these items; report and record status of the items and modification requests; ensure completeness, consistency, and correctness of the items; and control storage, handling, and delivery of the items. (ISO)"
Rational Unified Process, The: An IntroductionAddison-Wesley, 2003

Configuration and change management is a core supporting discipline in the RUP.