Private Practice is a spin-off of the highly popular ABC series Grey s Anatomy starring Kate Walsh as Dr. Addison Forbes Montgomery, a renowned neonatal surgeon. After realizing that her life isn t advancing at Seattle Grace, Addison packs her bags and heads off to Santa Monica to start a new life. She reunites with her newly divorced med school friends, Naomi (Audra McDonald) and Sam (Taye Diggs), and joins them in the chic private practice along with the other doctors on staff.