The Olney-Margolies Athletic Center (OMAC) was dedicated in 1981. Named for it's two principal donors, both members of the Class of 1936, Joseph Olney and Moe Price Margolies, it houses offices, locker and shower rooms, training support facilities, a large multi-purpose, open cage area which contains a 200-meter indoor track, five indoor tennis courts, and multiple intramural basketball courts.

Housed within the OMAC are the main offices for many Brown athletic teams, including football, baseball, and field hockey. Sitting atop the OMAC is Warner Roof, the home of Brown Field Hockey and the practice field for men's lacrosse. The facility has lights for night time play and bleachers at one end of the field, along with space on the sidelines to catch the action.