People often equate actors with roles they play, and 10 seasons into “NCIS” some folks think Mark Harmon is Leroy Jethro Gibbs.

“There’s an honor, focus and moral dedication that exists between the man, the actor and character,” says “NCIS” exec producer-showrunner Gary Glasberg. “Mark’s abilities and talent that have brought Gibbs to life. If there’s any blurry line between the two, that’s because Mark is that good of an actor.”

Unlike Gibbs, Harmon’s a family man with playful side. Andlike Gibbs, he’s a principled man of integrity.

“He was one of the first to say it’s our duty, as a family, that when someone’s having a bad day we need to carry them through,” says co-star Cote de Pablo. “That kind of attitude is very team-oriented.”

Harmon’s team concept extends beyond cast and exec producers.

“Mark’s the kind of guy who’s very close to the crew,” de Pablo adds. “He never cuts the line. He always goes to the back of the line when he’s getting lunch. If someone doesn’t have a chair, he’s always the first to offer his.”

Rocky Carroll, who worked with Harmon 15 years ago on the CBS hospital drama “Chicago Hope,” says while Harmon has evolved as an actor and a person over time, much remains the same.

“Guys like Mark tend to hang around for decades because they have this everyman quality that’s very relatable,” Carroll says. “You get that sense that he’s a moral person who lives by his own standards, but has a true sense of right and wrong.”

“NCIS” exec producer Charles Johnson says Harmon’s work ethic pays off.

“People like Mark amaze me because they work really hard at studying their characters. There’s such an ease with him that he makes it look effortless,” Johnson says, comparing Harmon’s work demeanor to James Garner.

Director Tony Wharmy adds, “He’s one of the most committed professional actors I’ve ever worked with, and I’ve worked with quite a few; people like John Gielgud and Anthony Hopkins, and Mark’s in that category.”