What are some movies that started relationships between the actors/actresses?

Katharine Hepburn and Spencer Tracy met when filming Woman of the Year and had a 27 year love affair.

Gigli: Jennifer Lopez & Ben Affleck, or Bennifer if you like.
Dream House: Rachel Weisz & Daniel Craig
Inner Space: Meg Ryan & Dennis Quaid
Proof of Life: Naughty Meg again, this time with Russell Crowe

Kristen Stewart and Robert Pattinson with Twilight series.

Jennifer Aniston has had a relationship with just about every penis-weilder she costarred with.

Jim Carrey and Jeff Daniels- Dumb & Dumber. ;-)

Darn I only thought of Mr. And Mrs. Smith for Brangelina, and Twilight for Robsten. My two have already been mentioned. :(

Cleopatra; Richard Burton and Elizabeth Taylor

Roy Rogers and Dale Evans met in 1944 when they were both cast in “The Cowboy and The Senorita.” They married three years later and stayed married for 51 years.

Jennifer Garner and Ben Affleck went into a relationship after filming Daredevil together.

Caveman – Barbara Bach and Ringo Starr

@janbb “Katharine Hepburn and Spencer Tracy…27 year love affair.”

At least for me, the sweetness of that affair gets spoiled by the fact that Spencer Tracy was married (to someone else) throughout.

Humphrey Bogart and Lauren Bacall met while filming “To Have and Have Not.”

Charles Chaplin and Georgia Hale in The Gold Rush

Gary Cooper and Ingrid Bergman in For Whom The Bell Tolls

Clark Gable and Loretta Young in the Call of the Wild.

it happens a lot

@SadieMartinPaul I wasn’t judging it one way or the other; just answering the question.

@janbb Oh, I wasn’t accusing you of judging, or even of making any subjective observations. I was just going off on my own tangent about the Hepburn-Tracy affair. It’s often heralded as one of Hollywood’s great love stories; to my old-fashioned sense of morality, it was protracted adultery. I’m not saying that either party was a bad person; I simply find adultery, especially when it’s so publicly known, to be unsavory.

@SadieMartinPaul I agree!

@janbb Yep. Years ago, I saw an interview with Katherine Hepburn. She talked about how when Spencer Tracy passed away, she couldn’t go to his funeral or memorial service. Despite all those years she’d spent with him, the man had a wife. It was the wife’s place to be there, and Hepburn knew better than to act inappropriately, show up, and cause a scandal. Very sad and unfortunate.

Tim Robbins and Susan Sarandon met filming “Bull Durham”