The Helping Adolescents Thrive toolkit, developed by the World Health Organization and UNICEF, provides programmatic guidance, based on evidence-based guidelines, for people working in the health, social services and education sectors on how to implement mental health promotive and preventive interventions that are appropriate to local needs and the contexts where adolescents live. The toolkit covers the legal foundations required for such programmes to succeed, the features of environments that are conducive to the well-being of adolescents, what support should be provided to parents and other caregivers, and psychosocial interventions that work.