<P> Kathleen Erin Walsh ( born October 13 , 1967 ) 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 . </P>
who plays addison shepherd on grey 's anatomy
Kathleen Erin Walsh