Rob Lowe Sam Seaborn Actor Martin Sheen President Josiah "Jed" Bartlet Actor Bradley Whitford Dep. Chief of Staff Josh Lyman Actor John Spencer Chief of Staff Leo McGarry Actor Richard Schiff Communications Dir. Toby Ziegler Actor Allison Janney Press Secretary Claudia Jean "C.J." Cregg Actor Dulé Hill Charlie Young Actor Janel Moloney Donna Moss Actor Stockard Channing Abigail "Abbey" Bartlet Actor Emily Procter Ainsley Hayes Actor Adam Arkin Dr. Stanley Keyworth Guest Star Kathleen York Andrea Wyatt Guest Star NiCole Robinson Margaret Guest Star Alanna Ubach Celia Walton Guest Star Carmen Argenziano Leonard Wallace Guest Star Nancy Cassaro Janet Price Guest Star Basil Wallace McKonnen Loboko Guest Star Paul Fitzgerald Casey Reed Guest Star Devika Parikh Bonnie Guest Star Kim Webster Ginger Guest Star Kris Murphy Katie Witt Guest Star Aaron Sorkin Executive Producer, Writer Thomas Schlamme Executive Producer John Wells Executive Producer Michael Hissrich Producer Kristin Harms Producer Llewellyn Wells Producer Christopher Misiano Director