Gary Yates is Security Guard in The Maestro (Season 7 Episode 3).
Gene Dynarski is Izzy Mandelbaun Jr. in The English Patient (Season 8 Episode 17).
Gene Dynarski is Izzy Mandelbaun Jr. in 
George C. Simms is Man #2 in The Robbery (Season 1 - Episode 3) and FBI Man in The Baby Shower (Season 2 - Episode 10).
George Murdock is Yuri Testikov in The Marine Biologist (Season 5 Episode 14).
George Wallace is the doctor in the final scene of The Checks (Season 8 Episodes 7).
Glen Chin is Harry Fong in 
Gordon Jump is Mr. Thomassoulo in The Butter Shave (Season 9 Episode 1) and in The Voice (Season 9 Episode 2).
Gregory T. Daniels is Man on Corvette in The Parking Garage (Season 3 Episode 6).
Harris Shore is the first Mr. Lippman, Elaine's boss at Pendant Publishing, in The Library (Season 3 - Episode 5).
Harry van Gorkum is Craig Stewart in The Wig Master (Season 7 Episode 19).
Henry Woronicz is Father Curtis in The Yada Yada (Season 8 Episode 19) and in The Burning (Season 9 Episode 16).
Hiram Kasten is Michael, Elaine's co-worker at Pendant Publishing in The Fire (Season 5 Episode 20).
Ian Abercrombie is the Justin Pitt in The Chaperone (Season 6 Episode 1).