Marina Sirtis (pronounced "Sir-tay") is a British-American actress best known for her role as half-human half-Betazoid Counselor Deanna Troi on the television and film series Star Trek: The Next Generation, appearing in 177 episodes from 1987-1994.
She also provided the voice of Demona in the animated series Gargoyles.
She is noted for appearing in the Oscar-winning movie Crash, as well as a semi-regular on the sitcom Girlfriends.
Along with Jonathan Frakes, Armin Shimerman, John de Lancie, Michael Ansara and Richard Poe, she is one of only six actors to play the same character on three different Star Trek series.
She played Counsellor Deanna Troi in Star Trek: The Next Generation (1987), Star Trek: Voyager (1995) and Enterprise (2001).