The Mountain West Conference (or MWC), the youngest of the college athletic conferences affiliated with the NCAA’s Division I FBS (I-A), officially began operations in July 1999. Geographically, the MWC covers a broad expanse of the western United States, with member institutions located in California, Colorado, Nevada, New Mexico, Texas, Utah, and Wyoming. Craig Thompson has served as Commissioner of the MWC since its founding in 1999.

Charter members included Air Force, BYU, Colorado State, New Mexico, San Diego State, UNLV, Utah, and Wyoming. Prior to forming the Mountain West Conference, seven of the eight charter members had been longtime members of the Western Athletic Conference; half were WAC charter members at its formation in 1962 - UNLV had only joined the WAC in 1996.

The WAC expanded from 10 to 16 universities in 1996, absorbing three teams from the defunct Southwest Conference (Rice, SMU, and TCU), adding two from the from the Big West (San Jose State and UNLV), and Tulsa from the Missouri Valley. After three football seasons, most of the pre-expansion members decided the that the new WAC was oversized, and departed to form the Mountain West Conference. The MWC added a ninth team in 2005: TCU, also a former WAC member, joined after four seasons in Conference USA.

A lesser known "Mountain West Athletic Conference" existed from 1982-88, sponsoring championships for women’s sports at Big Sky Conference institutions. The Big Sky absorbed the MWAC in 1988, forming one league for both men's and women's competition.