Drug abuse is one of the biggest social and health-related problems of today’s world, in both adults and youngsters. Addiction is a chronic and recurrent disease that can be caused by various psychoactive substances. Addiction prevention programs play an increasingly important role today. Prevention of addiction in youth involves a number of measures and procedures that help detect addictive behavior, and that empower users, families, and professionals. There are three levels of prevention. The primary level consists of informing the individual about the harmfulness of narcotics, the secondary level focuses on working with people suffering from addiction, and the tertiary seeks to reduce the harm of addictive behavior. Today, prevention is divided into universal, selective, and initiated. Various factors relating to the individual, their family, or their surroundings, can contribute to the prevention of addiction. It is the obligation of the society and the state to help the individual in combating addiction because it is they who determine what type of behavior is acceptable or is not. The addiction prevention system of the Republic of Croatia is carried out in the local communities and at the state level as well. Various experts participate in and implement prevention programs, including experts in the field of social welfare. Social workers have an important role in addiction prevention, but also in the treatments and resocialization of individuals.