Shapiro began his career as an independent film distributor in 1974 by starting International Harmony which distributed cult classics TunnelVision, Neil Young's Rust Never Sleeps, Bob Marley's Reggae Sunsplash, The Sex Pistols' DOA, and Tarzoon: Shame of the Jungle.

As a producer, Shapiro's credits include Mondo New York and Comedy's Dirtiest Dozen, which helped launch the careers of Tim Allen, Chris Rock, and Otto & George.

The New Yorker noted the importance of Chris Rock's appearance in Comedy's Dirtiest Dozen, saying it "helped earn him a place in the cast of 'Saturday Night Live', two years later, and that attitude helped make him the defining comic of the hip-hop generation.

"[3] Shapiro also produced the 72-hour live webcast of Woodstock '99, notable for being one of the largest of its kind at the time.

Shapiro is the founder and president of iConstituent, which provides online communications to the United States Congress.