Mock has volunteer with Equality Illinois, Orgullo en Accion, Association of Latin Men in Action, Lambda Legal, AIDS legal Council, About Face Theatre, Bailiwick Theatre. He has been a board member with Equality Illinois, Orgullo en Accion, and About Face Theatre. He is a founder of Orgullo en Accion and the Equality Illinois’ Capitol Club. He and his partner Bill Rattan are contributors to numerous gay and AIDS groups.

Mock has published several books about gay and Latino issues.

Writes Mock: "I seroconverted positive to HIV, the virus that causes AIDS, in late 1995. I was an obstetrician, so I immediately told my boss who was also gay. He wanted me to stay and continue working, since I was still healthy, but my lawyer advised me to go on disability. It was a big change. My relationship with my first lover was strained because he was HIV negative. We moved to Phoenix and I did not like it there. We finally broke off the 15-year relationship. Then I met Bill. It was love at first sight. Still we had problems because I went from working 80 hours a week to doing nothing. That was why Bill, to keep me busy, suggested I started putting in writing all of the stories I was always telling him. That’s how I became a writer."