Alain Morel, a psychiatrist and director of a treatment center for substance abusers, proposes a new strategy for preventing risky substance use. Drawing on his experience as a clinician working with young people who have problematic cannabis use, he emphasizes that the time has come to implement early detection for these young people. But this is only one aspect of a broader strategy. Above all, we must support young users in new ways, better train professionals, and enable parents and peers to play a role. And, ultimately, make it a political priority for prevention.