Toussaint appeared in the 1984 music video for Bon Jovi's song "She Don't Know Me", Bob Seger's 1986 song "Like A Rock", and in the 1987 music video for SAGA's song "Only Time Will Tell".

From 1988 to 1989, she was a regular cast member in the popular CBS prime time soap opera Dallas as "Tracey Lawton", and from 1996 to 1997 in The WB prime time soap opera Savannah. She also appeared in Cheers, Star Trek: The Next Generation (as Ishara Yar in the episode "Legacy", 1990), Melrose Place, Matlock, Babylon 5 (episode "Revelations", 1994) and Martial Law. In July 2006, she began appearing on The Young and the Restless in the recurring role of Hope Wilson.

She is married to actor Jack Coleman; they have a daughter, Tess, born in 1999. She is often mistaken for actress Linda Hamilton. She is the elder sister of David Toussaint.