Government CCBs are established for major acquisition programs. (Contractors also employ a similar process for their internal configuration control.) CCBs are usually comprised of the joint command or agency body chartered to act on class I ECPs and requests for major or critical deviations. The program manager is normally the chairperson of the CCB and makes the decisions concerning all changes brought before the CCB. The CCB is a program management process used by the program manager to ascertain all the benefits and the impacts of the change before the decision is made. When a decision is rendered, the CCB chairperson approves a CCB directive, or equivalent letter/memorandum, directing the appropriate implementing actions to be completed.