Dillon made her Broadway debut as an understudy for the roles of Jill Mason and the Nurse in Peter Shaffer's Equus in 1977.
[3] Her other theater credits include Agnes of God, The Corn is Green, Hay Fever,[4] Come Back, Little Sheba, Three Sisters,[5] and Our Town.
On television, Dillon was featured in Mary and Rhoda and has appeared in all three current shows in the Law & Order franchise.
Her screen credits include The Money Pit, A Shock to the System, Gods and Generals, and Duane Hopwood.
Dillon was also featured in the Disney Channel made-for-tv comedy film Lots of Luck, alongside Annette Funicello and Martin Mull.