Adam Nathaniel Yauch (August 5, 1964 – May 4, 2012) was an American rapper and songwriter best known as a founding member of hip hop trio the Beastie Boys. He was frequently known by his stage name, MCA and sometimes worked under the pseudonym Nathanial Hörnblowér.
Yauch was a practicing Buddhist. He became an important voice in the Tibetan independence movement. He created the Milarepa Fund, a non-profit organization devoted to Tibetan independence, and organized several benefit concerts to support the cause, including the Tibetan Freedom Concert.