Martin Sheen President Josiah "Jed" Bartlet Actor John Spencer Chief of Staff Leo McGarry Actor Rob Lowe Sam Seaborn Actor Bradley Whitford Dep. Chief of Staff Josh Lyman Actor Richard Schiff Communications Dir. Toby Ziegler Actor Allison Janney Press Secretary Claudia Jean "C.J." Cregg Actor Moira Kelly Mandy Hampton Actor Dulé Hill Charlie Young Actor Janel Moloney Donna Moss Actor Tim Matheson Vice President John Hoynes Guest Star Timothy Busfield Danny Concannon Guest Star John Amos Percy Fitzwallace Guest Star Elisabeth Moss Zoey Bartlet Guest Star Michael O'Neill Secret Service Agent Ron Butterfield Guest Star Jorja Fox Agent Gina Toscano Guest Star Kathryn Joosten Mrs. Landingham Guest Star NiCole Robinson Margaret Guest Star Devika Parikh Bonnie Guest Star Kim Webster Ginger Guest Star Suzy Nakamura Cathy Guest Star Kris Murphy Katie Witt Guest Star Ralph Meyering Jr. Tom Guest Star Aaron Sorkin Executive Producer, Writer Thomas Schlamme Executive Producer, Director John Wells Executive Producer Kristin Harms Producer Llewellyn Wells Producer