Nunn–McCurdy Amendment

The Nunn–McCurdy Amendment or Nunn–McCurdy Provision, introduced by Senator Sam Nunn and Congressman Dave McCurdy in the United States 1982 Defense Authorization Act and made permanent in 1983, is designed to curtail cost growth in American weapons procurement programs.

It requires notification of the United States Congress if the cost per unit grows of more than 15% beyond what was originally estimated, and calls for the termination of programs with total cost growth greater than 25%, unless the Secretary of Defense submits a detailed explanation certifying:
 * 1) the program is essential to national security, that no suitable alternative of lesser cost is available,
 * 2) new estimates of total program costs are reasonable, and
 * 3) management structure is (or has been made) adequate to control costs.

Very rarely is a program actually cancelled under this provision—Congress normally regards the explanations from the Secretary of Defense as acceptable—but it has led to many changes to project management. SBIRS has been affected by the provision in 2002 and again in 2005, and the NPOESS meteorology satellites have been redesigned with lesser capabilities after being affected by the provision.

In 2006 the House of Representatives proposed amending the provision to require a detailed explanation, including information about possible alternatives, at the 15%-cost-growth mark.

However, in 2009 and 2011 the US Army's FCS and USMC EFV vehicle programs were both cancelled due to cost overruns.