Online and video games are arguably the most lucrative sector of the entertainment industry, with an estimated 2 billion global players and annual revenue exceeding that generated by films, television and books. But with profits and popularity can also come societal problems. The world’s biggest gaming company by revenue, the Chinese firm Tencent , has voluntarily tightened restrictions for those aged under 18 for its flagship title, Honour of Kings . Beijing, worried about addiction, already has some of the tightest controls and the new limits aim to further curtail spending and playing time . It is a laudable move, but ultimately, it is up to parents and children to determine the right balance. Beijing restricts online gaming for minors to 90 minutes a day and three hours on holidays, and requires companies to verify players’ ages and identity. Tencent, under pressure from state media which had labelled gaming as “spiritual opium” , acted on its own accord, reducing the limits by an hour and prohibiting playing between 10pm and 8am. Those under the age of 12 are banned, 12- to 16-year-olds cannot spend more than 200 yuan (US$31) a month and those between 16 and 18 will be capped at 400 yuan. Gaming stocks understandably plummeted after the announcement. Honour of Kings made Tencent US$2.6 billion from in-app purchases last year, with an average of 100 million users a day, making it the world’s most popular and profitable online game. But the gaming industry has to be mindful that the addictive features often built into its titles to maximise profits can have a negative impact for some children and their families. Tencent narrows kids’ playing time on flagship game Honour of Kings That is why the World Health Organization in 2019 added “gaming disorder” to its classification of diseases, defining it as excessive and irrepressible preoccupation with video games, resulting in significant personal, social, academic or occupational impairment. In the worst cases, large bills can be racked up and health, schoolwork and family ties can suffer. Beijing is right to be concerned and companies have an obvious role in helping to ensure a healthy online environment. But parents have the best chance of moderating the behaviour of their children.