Major sports leagues have embraced legalized gambling across the U.S. At the same time, they recognize the need to act as good corporate citizens — and are urging fans who gamble to know their limits.

The National Basketball Association, Major League Baseball and the National Hockey League have teamed up for “Never Know What’s Next,” a 30-second ad that encourages responsible betting in sports. The campaign, launched Tuesday, directs fans to the National Council on Problem Gambling’s responsibleplay.org website.

The spot (watch below) is supported by sportsbook operators DraftKings, Fanatics Sportsbook, FanDuel and Penn Entertainment (operator of the recently launched ESPN BET). The “Never Know What’s Next” PDA premieres on TV Nov. 21 during the NBA’s In-Season Tournament Cleveland Cavaliers-Philadelphia 76ers game on TNT at 7:30 p.m. ET and on NBA, MLB and NHL social accounts.

“[N]o one wins all the time,” the PSA’s voiceover concludes. “So if you bet, bet responsibly. And always set a limit.”

The NFL also has a responsible-betting campaign, with a PSA this season featuring former quarterback Kurt Warner with the tagline “Stick to Your Gameplan.”

The “Never Know What’s Next” spot features game footage from the NBA, MLB and NHL “to demonstrate the inherent unpredictability of sports,” per the leagues. According to the NBA, MLB and NHL, “At the heart of this campaign is an educational message reminding bettors that betting is a form of entertainment and should be done so responsibly. This campaign seeks to inform bettors, with the critical message that there are no ‘locks’ and no ‘easy money’ in sports betting.”

“Whether it’s a game winning shot from beyond half court, a game changing save on the ice or a walk-off home run, the campaign reminds fans that every play, every shot, every swing is unpredictable,” the leagues said in announcing the PSA.

“Working with our fellow sports leagues, gaming operator partners, and responsible gaming partners gives added weight — particularly for young bettors — to this shared priority of making an impact on responsible gaming education across the United States,” Scott Kaufman-Ross, NBA SVP, head of gaming and new business ventures said in a statement.

MLB’s Casey Brett, SVP of business development, added, “It’s paramount that when our fans bet, they know how to do so responsibly — and this initiative is just one small but important part of our continued commitment to ensuring sports betting stays safe for all who choose to wager.”

“This campaign continues our ongoing commitment to educating fans about the importance of responsible betting,” commented Keith Wachtel, the NHL’s chief business officer. “With more fans than ever having the opportunity to legally bet in their home states, it is imperative that we work with our media and sportsbook partners, as well as with our friends at the NBA and MLB, to inform and emphasize the risks and encourage the importance of setting limits and betting responsibly, especially among our growing fanbase in the younger demographic.”

Watch the “Never Know What’s Next” spot: