Recurring
Brett Butler as Brett, the female bartender at the Merry Peasant tavern that Charlie frequents.
Michael Boatman as Michael, Charlie's neighbor and friend, who is in the real estate business. He is always freeloading off Charlie while listening to him talk about his romantic pursuits. He is especially unlucky at love. (episodes 1–55, guest episode 95)
James Black as Cleo/Derek, a "gay" member of Charlie's prison anger-therapy group. In "Charlie's Patient Gets Out of Jail", Cleo is released on parole and reveals to Charlie that his real name is Derek and that he had a wife before going to prison, claiming he's only "prison gay".
Darius McCrary as Donovan, a "prison gay" member of Charlie's prison anger-therapy group; Cleo/Derek's romantic partner. He acts effete in prison, but relatively masculine on the outside. (episodes 1–42)
Stephen Taylor as Wayne Dwayne Earl, a member of Charlie's prison anger-therapy group. Despite a seemingly pleasant, philosophical demeanor, he's revealed to have been a dangerous serial killer.
Aldo Gonzalez as Ernesto Sylvia, a member of Charlie's prison anger-therapy group.
Martin Sheen as Martin Goodson, Charlie's father. (episodes 10–100)
Steve Valentine as Dr. Moore, a rival psychiatrist whom Charlie considers his arch enemy. (episodes 13–44)
Anna Hutchison as Sasha, a hooker who is occasionally a real girlfriend for Charlie. She and Charlie are briefly married after a wild night in Las Vegas. (episodes 49–92)
Ajay Mehta as Sanjay Patel, Lacey's father.
Meera Simhan as Mira Patel, Lacey's mother.
Schuyler Helford as Sateen, Lacey's sister, who is frequently competing with her.
Michael Gross as Dr. Randy Warren, a "psychic psychologist" whom Charlie exposes as a fraud. He briefly appears in Charlie's prison therapy group later on. (episodes 77–80)
Elaine Hendrix as Warden Hartley, the new warden at the prison where Charlie and Jordan work. (episodes 79–83)