Young adults are a risk group for gambling harm. There are indications that the normalization of gambling, such as exposure to loot boxes/ sports betting in daily life, can serve as a stepping stone to playing more and other types of games of chance. For the Dutch situation, it is not yet known how many young adults engage in gambling, which young adults are at extra risk and how gambling can grow into a problem or can cause harm. This knowledge is essential before effective preventive measures can be taken. This project will provide this crucial knowledge by examining the prevalence of gambling and which demographic, cognitive, psychological and social factors are predictive of (problematic) gambling consumption in general and its increase over time. This knowledge will be supplemented with interviews with young adults, parents, (sports) teachers, and healthcare professionals, and an inventory will be made of prevention measures that are considered useful in preventing gambling harms.