Some of the prints hanging on the wall of Rachel Zane's office are the works of Patrick J. Adams (Mike).
Both Michelle Fairley (Ava Hessington) and Conleth Hill (Edward Darby) are actors from the HBO series Game of Thrones (2011). Michelle Fairly played Caitlyn Stark and Conleth Hill plays Varys.
Louis and Harold mention The Sound Of Music. Denise Crosby, who would go on to play Fay Richardson the Special Master, was at one point married to Julie Andrews' stepson Geoffrey Edwards for a brief period of time.