Mark Feuerstein starred opposite Katie Homes in the feature film thriller, Abandon directed by Oscar-winner Stephen Gaghan. He portrayed Mel Gibson's sidekick in the comedy hit What Women Want. Feuerstein's other film credits include The Muse, starring Albert Brooks and Sharon Stone; the courtroom drama Rules of Engagement, opposite Tommy Lee Jones and Samuel L. Jackson; the romantic comedy Woman On Top, starring Penelope Cruz; and Practical Magic opposite Sandra Bullock.

Feuerstein had a key recurring role in the award-winning television drama, The West Wing. He starred in the NBC series Good Morning Miami, a comedy about a producer who takes a job on the lowest-rated morning show in the country to pursue the love of his life. He had a guest-starring role on the series Ally McBeal opposite Calista Flockhart, and a recurring role opposite Sela Ward and Billy Campbell on the drama Once and Again. His television credits also include Sex and the City, Conrad Bloom, Fired Up and Caroline in the City.