Who has starred in the most successful TV series?

He also starred on the soap One Life to Live.

If we were including TV miniseries, Richard Chamberlain would have to be somewhere near the top.

Per Wikipedia, Rescue 911 had 186 episodes and two specials over seven seasons. Tek War ran for 22 episodes and two seasons. So Rescue 911 more than qualifies for the OP.

Since three series’ is enough to get a mention in this thread I think we need to give a shoutout to Dame Judi Dench who was lead in the 80’s A Fine Romance and then later As Time Goes By which went on for bloody ever, plus something called Cranford which I’ve never watched but does have the requisite three (British) seasons. All while keeping up a decades-long A-list movie career

Fun fact: Dame J first starred in a series in 1959 and has been playing leads ever since

So, is Wikipedia the reliable source over IMDb?

While not the star, Richard Broder had an impressive run as the same character on 3 different, very successful series as Dt. Munch on Homicide, Law & Order, and L & O SVU.

Richard Belzer, and he was only a regular on two series, Homicide: Life on the Streets and Law & Order: SVU. He also appeared as Det. Munch as a guest star in individual episodes of several other shows, including Law & Order, and The X-Files (!).

I’m not sure what you are arguing. IMDB is obviously wrong. Shatner was the host and there were a hell of a lot more than 18 episodes. If you start looking at the individual episodes on IMDB you’ll notice that many have no cast listed. IMDB is only accurate with old shows if someone bothered to index it.

Honorable mention to Tom Selleck. Magnum P.I. and Bluebloods. He also did 9 or 10 Jesse Stone made for TV movies.

Yes Belzer. Stupid autocorrect.

Cranford is worth watching.

On the one hand, I look at the title of the show… but then I check IMDB, and I see it described as “Neighbor Blanche Morton frequently joined Gracie in escapades which annoy hubby Harry and provides George with an opportunity to offer a humorous soliloquy.” Bea played Blanche, and I’ll call that top billing. She was also in all 292 episodes.

By the way, some of the cites listed so far are for work as a host/presenter or for voice work on an animated series. If we’re counting those, we’re going to wind up with a very different list.

For example, Frank Welker has provided voices for dozens of animated series. While most of them only lasted a single season, he voiced one or more main characters in quite a few that lasted at least three seasons. The various iterations of Scooby-Doo alone are going to out-do any live action actor by a mile, and even if we count all iterations of Scooby-Doo as a single show, he’s also got Gargoyles, The Transformers, The Smurfs, Spider-Man and His Amazing Friends, Inspector Gadget, Dungeons & Dragons, Muppet Babies, Snorks, The Real Ghostbusters, Adventures From the Book of Virtues, Curious George, The Garfield Show, and about as many 3+ season shows where he provided voices for “various characters and animals.”

It does look it! And she’s on my personal list of ‘actors who can pick a good project’ too

Try five. There was also George and Leo (His full name is George Robert Newhart).

Gene Barry starred in Bat Masterson, Burke’s Law, and The Name of the Game, and had a bunch of other roles that don’t qualify as being the star for two years.

I tend to trust Wiki. And Rescue 911 airs every weekday on GetTV. I’ve watched way more than 18 episodes. It wouldn’t be worth stripping it on weekdays if 18 episodes were all there were. A show needs at least 100 episodes to make daily syndication worthwhile.

IMDB lists 186 episodes of Rescue 911 - some of them have only one or two people listed in the “cast” and don’t include any host. It seems pretty clear that the 18 episodes that Shatner is credited with on his IMDB page are just the ones that someone bothered to update the episode page for.

And won Emmys for each.

Betty White had genuine lead roles on Hot In Cleveland and Golden Girls, as well as four other series that didn’t last the required three years. But she did four years on Mary Tyler Moore and literally hundreds of episodes of Match Game. I think that should count if only because she’s Betty White.

If we expand this to something other than sitcoms and dramas, Barbara Walters has headlined a bunch of very highly rated and long-lasting shows (The Today Show from 1963-76, Not For Women Only, The View, 20/20, Entertainment Tonight). Rosie O’Donnell has headlined many highly rated shows (Stand Up/Stand Up, The Rosie O’Donnell Show, The View, The Talk) and quite a few less popular ones that might squeak by to qualify. Tom Snyder had at least three late night talk shows, but realistically they were all the same show with some long interruptions. Ditto Dick Cavett.