Kate Walsh played Dr. Addison Montgomery on Grey's Anatomy.
Kathleen Erin Walsh -LRB- born October 13 , 1967 -RRB- is an American actress and businesswoman .. Her roles include Dr. Addison Montgomery on the ABC television dramas Grey 's Anatomy and Private Practice , Rebecca Wright on the short-lived NBC sitcom Bad Judge , and Olivia Baker on the Netflix drama series 13 Reasons Why .. Addison Montgomery. Addison Forbes Montgomery. ABC. American Broadcasting Company. Private Practice. Private Practice ( TV series ). NBC. NBC. Bad Judge. Bad Judge. Netflix. Netflix. 13 Reasons Why. 13 Reasons Why