Though Jennifer Aniston and Vince Vaughn, the co-stars of “The Break-Up,” won’t speak a peep about their relationship, they’re the latest and greatest celebrity pairing. And they’re taking part in a grand Hollywood tradition: meeting on set.

Tinseltown has long been populated by couples whose romances moved from on-screen to real life. Katharine Hepburn and Spencer Tracy, Elizabeth Taylor and Richard Burton, and Humphrey Bogart and Lauren Bacall all captivated audiences and cultivated personal partnerships.

Those relationships, however, seemed to stick around longer than more recent couplings like Jennifer Lopez and Ben Affleck, whose pairing helped create buzz for their (doomed) flick “Gigli,” but ended shortly thereafter.

In past years, actor couples seemed to stick it out for the long haul. Hepburn and Tracy’s relationship lasted both on- and off-screen through more than eight movies, beginning with “Woman of the Year” (1942). Though Ms. Taylor is no paragon of marital stability, she and Burton collaborated on a handful of films following their debut in “Cleopatra” (1963) and at home for years. Bogart and Bacall lasted through 12 years of movie-making, beginning with “To Have and Have Not” (1944).

But today’s onscreen celebrities often seem to have trouble distinguishing their work (acting) from real life, a phenomenon which has led to the growing trend of serial movie set daters.

Brad Pitt was linked with Gwyneth Paltrow (whom he met on “Seven”) and Juliette Lewis (“Too Young To Die”). He met his current gal pal, Angelina Jolie, on the set of “Mr. and Mrs. Smith” – much to the detriment of his marriage with Ms. Aniston.

Penelope Cruz caught the bug as well, pairing up with Matt Damon (whom she met on “All the Pretty Horses”), Tom Cruise (“Vanilla Sky”), and her current flame Matthew Mc-Conaughey (“Sahara”). And Mr. Mc-Conaughey himself is perhaps the worst offender, having dated a bevy of Hollywood leading ladies, including Patricia Arquette, Sandra Bullock, Ashley Judd, and Ms. Cruz, almost all of whom he’s met on set.

Even the HBO series “Entourage,” set in Hollywood, acknowledges this time-honored tradition. One significant plot theme last season – which will surely return when the series kicks off June 11- revolves around the lead character, Vincent Chase, starting up an on-set romance with co-star Mandy Moore while filming “Aquaman.”

But the real-life romances of Hollywood’s biggest stars usually provide even better drama than the fictional scenes shown on screen, as actors trade partners on and off the set as quickly as they change their hair color. Maybe Ms. Aniston and Mr. Vaughn’s tete-a-tete won’t last a lifetime, but they may not need to worry. After all, they’ve both got plenty of movies lined up for the future. Potential dates can’t be far behind.