Friends made international stars of Jennifer Aniston, Courteney Cox, Lisa Kudrow, Matt LeBlanc, Matthew Perry and David Schwimmer. But the show was so successful that A-Listers were practically queuing up to be a part of the programme. Some, like Tom Selleck, showed up throughout the ten-year run. Others, like Alec Baldwin or Denise Richards, dropped in for one-offs. Some, however, made more of an impression than others. Reese Witherspoon was so popular that she's returning for the much anticipated reunion episode.
Here are our twelve favourite celebrity appearances from our all-time favourite sitcom. Did yours make the list?

Reese Witherspoon
Reese was a Young Hollywood star when she was hired for a two episode role in Friends, having appeared in Legally Blonde and Cruel Intentions. She played Jill, Rachel's spoiled little sister whose eyes stray too Ross, leading to a huge argument with Rachel. Off-screen, Reese got on well with Jennifer Aniston. So much so that they starred in last year's The Morning Show.
READ MORE: Forget The Main Cast Of Friends: The Supporting Actors Are Also Making Thousands From Repeats