The idea for Baywatch came about after creator Gregory J. Bonann, while on duty as a real lifeguard, saved two children belonging to an MTM studio employee named Stu Erwin. The show was originally going to be called Aquatic Corps for Emergency Service (ACES) before being renamed Baywatch, after the rescue boats that patrolled Santa Monica Bay.

Baywatch was canceled by NBC after just one season, placing 73rd out of 103 shows in the ratings, partly because the production studio GTG went out of business due to high production costs. David Hasselhoff, along with the creators, revived the series for first-run syndication in 1991, after which it became a massive international hit reaching over 1.1 billion viewers weekly despite consistently negative reviews.

For its move away from Los Angeles due to rising production costs, the show initially filmed a pilot titled Baywatch: Down Under to relocate to Avalon Beach, Australia, but strong local opposition led the Pittwater Council to permanently ban future production there. Hawaii then offered large financial incentives instead, leading to the creation of Baywatch: Hawaii for seasons 10 and 11.

The original NBC theme song was 'Save Me' performed by Peter Cetera with Bonnie Raitt on guitar, but from the second season onward the syndicated version used 'I'm Always Here' by Jimi Jamison to save on royalty costs, which became the show's most iconic theme.

The famous red swimsuits worn by the actresses were modeled after those worn by real Southern California female lifeguards, originally designed for functionality rather than for sexy appeal. Each suit was custom-fitted per actress, with Alexandra Paul given a higher neckline and shorter cast members given higher-cut legs to create the illusion of height.

The recurring shots of cast members running across the beach in slow motion, especially in the opening credits, became known as 'Baywatch running' and turned into a trope frequently referenced in parodies of the show.

The show's audience was 65 percent female, with women aged 18 to 34 as its top demographic; producer Douglas Schwartz explained that focus groups revealed the appeal came from lead characters being strong, independent women who were heroic and equal to men.

Because 2018's 'remastered' high-definition version was actually re-created from tape rather than the original film, since the show had been edited on tape, the new cuts are not always shot-for-shot accurate and changed the aspect ratio to 16:9 widescreen, altering the field of view in various shots. Expired music licenses also forced many episodes to be cut or re-scored with 'soundalike' tracks chosen with the advice of original co-composer Cory Lerios.

The 2017 feature film adaptation, starring Dwayne Johnson and Zac Efron, spent years stuck in development hell after being first announced in 2004. Despite grossing $177.9 million worldwide against a budget of $65–69 million, it received negative reviews and earned five Golden Raspberry Award nominations, including Worst Picture and Worst Actor for Efron.