The 11th Infantry Regiment is a regiment in the United States Army. In 2007, the 11th Infantry was reflagged as the 199th Infantry Brigade, as part of the "Transformation of the US Army" effort. Today, the 11th Infantry Regiment is part of the Army's regimental system and is the primary regiment to which many Infantry School units are aligned.

The 199th Infantry Brigade (Light) is a unit of the United States Army which served in the Army Reserve from 1921 to 1940, in the active army from 1966 to 1970 (serving in the Vietnam War), briefly in 1991–1992 at Fort Lewis, and from 2007 as an active army training formation at Fort Moore.