Must See TV was an American advertising slogan that was used by NBC to brand its primetime blocks during the 1990s, and most often applied to the network's Thursday night lineup, which featured some of its most popular sitcoms and drama series of the period, allowing the network to dominate prime time ratings on Thursday nights in the 1980s and 1990s. Ratings for NBC's lineup fell during the mid-to-late 2000s. The slogan was retired in 2015 amidst NBC's transition to airing more drama series on Thursday nights. The branding returned for the 2017–18 television season but was removed for a second time in the winter of the 2020–21 television season.

Usage In popular culture, the phrase is most strongly associated with the network's entire Thursday night lineup, including both sitcoms and dramas, which dominated the ratings from the 1980s through the late 1990s.

As originally conceived, "Must See TV" originally applied to sitcoms only (dramas would normally be promoted separately), and for much of the 1990s the phrase was used several nights a week as an attempt at brand extension. At one point in the fall of 1997, the brand was used five nights a week, with four sitcoms a night from Monday to Thursday and two more on Sunday. NBC itself would later adopt the more common interpretation; the 2002 retrospective, 20 Years of Must See TV, focused on NBC's overall dominance on Thursday nights from 1982 onwards, and overlooked extensions such as "Must See TV Tuesday."

History First years By 1979, NBC had fallen to third place in the Nielsen ratings. Network executive Fred Silverman, who previously led ABC and CBS to the top of the ratings, joined the network the year before; however, he could not bring the same ratings success he had as programming whiz at the latter two networks, resulting in a string of new programs that were derided by critics and which were eventually cancelled after a few showings. The 1980–81 television season was the low point for NBC; as the network had only three shows in the Nielsen top 20; one of them was the sitcom Diff'rent Strokes, starring Gary Coleman and Conrad Bain, with several of its episodes revolving around serious issues such as racism, alcoholism, child abuse and others, which were dramatically explored. Debuting on Fridays and garnering modest ratings, Diff'rent Strokes entered NBC's Thursday night lineup for the 1981–82 season. Prior to the beginning of the season, Silverman left NBC in the summer of 1981, and was replaced by Brandon Tartikoff, who became a very important key point behind NBC's return to the top.

The 1981 fall season marked the very first time NBC made an attempt to create a two-hour comedy block on Thursday nights comprising the 8–10 p.m. slot, with Diff'rent Strokes being joined by the returning Harper Valley starring Barbara Eden, formerly from I Dream of Jeannie, and newcomers Gimme a Break!, starring Nell Carter as the housekeeper for a widowed police chief (played by Dolph Sweet) and his three daughters, and Lewis & Clark, a starring vehicle for Gabe Kaplan after Welcome Back, Kotter.

These four sitcoms were followed by the police drama Hill Street Blues, which premiered in January 1981, and chronicles the lives of the Metropolitan Police Department staff of a single police station located on Hill Street in an unnamed large U.S. city. While critically acclaimed, Hill Street Blues bounced to and from various time periods on Thursday, Saturday, Tuesday and Wednesday nights during its first season, which caused it to debut to poor ratings (87th out of 96 shows for the 1980–81 season) and became the lowest-rated program ever renewed for a second season at the time. NBC decided to move Hill Street Blues officially to Thursdays at 10 p.m., which resulted in a ratings success starting with its second season, and earning several industry awards, including a total of 26 Primetime Emmy Awards (out of 98 nominations) during its seven-season run, including four consecutive wins for Outstanding Drama Series from 1981–1984.

Midway through the 1981–82 season, Harper Valley and Lewis & Clark were removed from NBC's Thursday schedule, and later were canceled, being replaced by the Emmy-winning musical television series Fame, which was based on the 1980 film of the same name. That series was a critical success, receiving three consecutive nominations for an Emmy Award for Outstanding Drama Series, but losing all of them to Hill Street Blues.

Success in the 1980s Branding the quality Thursday night lineup began during the 1982–83 season, with NBC promoting Fame, Hill Street Blues, Taxi (which was renewed by the network after being canceled by ABC after four seasons) and new arrival Cheers, as "America's Best Night of Television on Television". Diff'rent Strokes and Gimme a Break! were moved to Saturdays at the beginning of the season, with Strokes remaining on that night until its cancellation in 1985 (only to be renewed by ABC for an additional season), and Break! returning to Thursdays following the underperformance of Taxi, which at mid-season, was moved to Saturdays, and later to Wednesdays, to be eventually canceled for a second time by NBC. Fame also ended its two-season network run on NBC to be revived the following season in first-run syndication. A mid-season replacement, Mama's Family, starring Vicki Lawrence, which debuted on Saturdays, moved to Thursdays during the summer, following Fame'''s removal from NBC's schedule.

Meanwhile, Cheers, which starred Ted Danson and Shelley Long (and later, Kirstie Alley), set in the titular bar in Boston, where a group of locals meet to drink, relax, socialize, and escape from their day-to-day issues debuted to critical acclaim, but ended its first season with unimpressive ratings. It was the fourth-lowest rated show for the 1982–83 season (74th out of 77 in that year's ratings), and was nearly canceled by NBC. However, Cheers was renewed for a second season, in large part due to Tartikoff's continued support of the show, as well as its slow increase in viewership during its summer reruns, garnering higher ratings than when it first premiered. Its first season received 13 Primetime Emmy Award nominations in 1983, and won five of them, including an award for Outstanding Comedy Series. Cheers remained one of NBC's most successful shows on Thursday nights, becoming a top-ten hit starting with its fourth season, and reaching number one during its ninth season, earning 28 Primetime Emmy Awards from a record of 117 nominations.

The 1983–84 season saw none of NBC's new fall shows renewed for a second season, and Thursday nights weren't the exception. One of the new shows that season, was the sitcom We Got It Made, starring Teri Copley as a woman who works as a maid for two bachelors in New York City, played by Tom Villard and Matt McCoy. While the series initially started with strong ratings, critics and the general public lambasted the show, which eventually damaged its viewership as the season progressed. In December 1983, NBC began making changes to its Thursday lineup in order to make room for soon-to-be hit shows to join Cheers, Gimme a Break! and Hill Street Blues.

One of these shows, Michael J. Fox's Emmy-winning sitcom Family Ties, which reflected the social shift in the United States from the cultural liberalism of the 1960s and 1970s to the conservatism of the 1980s, debuted on Wednesdays to a modest start, but moved to Thursdays midway through its second season, resulting in a ratings rise. Family Ties replaced Mama's Family, which was moved to Saturdays, along with We Got It Made, which was replaced by Cheers returning to its original 9:00 p.m. timeslot, remaining there for the rest of its run. The show that followed it, was Dabney Coleman's Emmy-nominated series Buffalo Bill, which debuted in the summer of 1983, and returned as a mid-season replacement for its second season, and featured the misadventures of an egotistical talk show host, played by Coleman, and his staff (including Geena Davis and Joanna Cassidy, who won a Golden Globe Award for her role). Despite having been nominated for eleven Primetime Emmy Awards during its run (including two for Outstanding Comedy Series), Buffalo Bill fared not-so-well in the ratings and was canceled by NBC after two abbreviated seasons. Brandon Tartikoff later wrote in his memoir The Last Great Ride (1992), that his biggest professional regret was cancelling the show.

Meanwhile, We Got It Made and Mama's Family were moved from Thursdays to Saturdays, where ratings for both shows dropped even further and later were canceled at the end of the 1983–84 season, before eventually being revived years later for syndication. In the spring of 1984, Buffalo Bill was replaced by another short-lived comedy The Duck Factory, becoming Jim Carrey's first lead role in a Hollywood production (coincidentally, Carrey previously guest-starred on an episode of Buffalo Bill, prior to the premiere of The Duck Factory). A mid-season replacement for that season, Night Court, set in the night shift of a Manhattan Criminal Court presided over by a young, unorthodox judge, Harold "Harry" T. Stone, played by Harry Anderson, nominated three times as Best Lead Actor in a Comedy Series at the Emmys for his role, and co-starring John Larroquette, who won four consecutive Emmys for Best Supporting Actor in a Comedy Series for his role as Dan Fielding, initially aired on Wednesdays. The series was moved to Thursdays during the summer, becoming another staple of NBC's Thursday comedy night in the following years.

What marked the beginning of NBC's dominance on Thursday nights was during the 1984–85 season, when the network premiered a new show to lead that evening: The Cosby Show, which focused on the Huxtables, an upper middle-class Black American family living in New York; the series was based on routines in Bill Cosby's stand-up comedy act, which in turn were based on his family life. The Cosby Show received critical acclaim, with TV Guide listing the series as "TV's biggest hit in the 1980s", adding it "almost single-handedly revived the sitcom genre and NBC's ratings fortunes". The enormous success of The Cosby Show, which earned a Primetime Emmy Award for Outstanding Comedy Series in 1985, and became the highest-rated sitcom and the third-most watched show overall of the 1984–85 season in the US, also helped the other shows on the Thursday lineup increase their ratings dramatically. Family Ties entered the top-ten for the first time; and both Cheers and Night Court entered the top-twenty; while Hill Street Blues remained steadily in the top-thirty.

Prior to the debut of The Cosby Show, CBS was the winner on Thursday nights in the early 1980s, with a powerful lineup consisting of Magnum, P.I., Simon & Simon and Knots Landing. However, that lineup began to lose strength by the mid-1980s, especially when Cosby debuted, which also marked a major turning point for NBC as well. The network rose to second place at the end of the 1984–85 season and later reached first place at the end of the 1985–86 season, with Cosby spending five consecutive seasons as the number-one rated show on American television, and tying with CBS' All in the Family, to become the only sitcoms in the history of the Nielsen ratings to be the number-one show for five seasons, earning several accolades, including six Primetime Emmy Awards from 23 nominations.