Anthony Edwards Dr. Mark Greene Actor George Clooney Dr. Doug Ross Actor Eriq La Salle Dr. Peter Benton Actor Noah Wyle Dr. John Carter Actor Julianna Margulies Head Nurse Carol Hathaway Actor Gloria Reuben Jeanie Boulet Actor Laura Innes Dr. Kerry Weaver Actor Alex Kingston Dr. Elizabeth Corday Actor Maria Bello Dr. Anna Del Amico Actor William H. Macy Guest Star John Aylward Guest Star Frances Sternhagen Millicent Carter Guest Star Mariska Hargitay Guest Star Bellina Logan Nurse Kit Guest Star Michael Beach Guest Star Paul McCrane Robert Romano Guest Star Trevor Morgan Scott Anspaugh Guest Star Clancy Brown Guest Star Jonathan Scarfe Chase Carter Guest Star Lily Mariye Nurse Lily Jarvik Guest Star Michael Crichton Executive Producer John Wells Executive Producer