Yauch learned to play the bass, and played his first show with the Beastie Boys - then still playing hardcore punk in the vein of Reagan Youth - on his 17th birthday, while still attending Edward R. Murrow High School in the Midwood neighborhood of Brooklyn. By the time Yauch was 22, producer Rick Rubin had taken the Beastie Boys under his wing and they had released their first album on Def Jam Records as a hip hop trio.

In addition to the Beastie Boys, Yauch is involved in many other activities. Although his family was Jewish, Yauch is also a practicing Buddhist, contributing to his political activism. He is actively involved with the Free Tibet movement, an organisation created to show solidarity with the plight of the Dalai Lama and to put pressure on the People's Republic of China to respect human rights in Tibet. Funds for the cause were also generated from the royalties to Buddhist-inspired Beasties tracks like Bodhisattva Vow. In 1996 Yauch helped organize the first Tibetan Freedom Concert in San Francisco, California. His wife, Dechen Wangdu, is from Tibet.

Under the pseudonym "Nathanial Hornblower", Yauch has directed many of the Beastie Boys' music videos. Yauch made his televised debut as Hornblower at the 1994 MTV Video Music Awards as he stormed the stage in costume to protest after REM won the award for Best Direction over the Spike Jonze directed Beastie Boys video "Sabotage". He also directed the upcoming Beastie Boys concert film Awesome; I Fuckin' Shot That!.

Yauch is also an avid skater.