Altman has had a successful career in acting for film, theatre, and television. Beginning his career on the stage, the Bronx native acted in such off-off-Broadway shows as The Brick and the Rose, Liverpool Fantasy, Romeo and Juliet and The Sea Gull in the early 80s. From there, Altman moved on to numerous films such as Glengarry Glen Ross, Rookie of the Year, Matchstick Men, and many others. His TV credits are just as vast, including The Sopranos, Suits, Damages, and numerous others. He is currently appearing in the television series Mr. Robot and Odd Mom Out.