Mark Suster is a prominent American businessman and investor, currently serving as a General Partner at Upfront Ventures, the largest venture capital firm in Los Angeles, a role he has held since 2007. Prior to his venture capital career, Suster was a two-time entrepreneur. In 1999, he co-founded BuildOnline, a construction collaboration technology business where he served as CEO. BuildOnline later merged with Citadon in 2006.