Born and raised in Philadelphia, Bob graduated from the William Penn Charter School and attended Yale University. His acting career began at Yale when he landed a leading role in Leonard Bernstein's “Mass”and later performed it in the European premiere of that work. Bob, then a biology major, abandoned his premed plans and graduated Magna Cum Laude with a B.A. in Drama at age 20. He moved to New York and studied acting at Circle in the Square. In 1977, he made his Broadway debut in the lead role of the comedy hit “Gemini”. The following season, he won the coveted part of Jack Lemmon's son in Bernard Slade's “Tribute”, re-creating his role in the Los Angeles production. In California, Bob has played leading roles at the Mark Taper Forum, The Pasadena Playhouse, the Berkeley Rep and other venues.
On television, Bob earned an Emmy Nomination for his role as Mr. Cutlip on “The Wonder Years. He received the Founders Award from Viewers for Quality Television for his combined work on that show and his starring role as Dr. Richard on the acclaimed Vietnam drama, “China Beach”. Bob is recognized around the globe for his curmudgeonly Holographic Doctor on seven seasons of “Star Trek: Voyager”. One of the two Voyager episodes Bob also directed, "One Small Step," was a moving tribute to the pioneers of space exploration. He has guest starred on many popular television series, starred as Commander Woolsey on “Stargate Atlantis” and plays recurring roles on CBS “The Code” and Apple Studio’s “Dickinson”. Bob has appeared in over two dozen films, including the Coen Bros comedy, “Hail Caesar” and pretty much anything ever directed by Joe Dante. Bob is on the Executive Board of the Planetary Society, the space Advocacy nonprofit cofounder by Carl Sagan and presently led by Bill Nye.