Based on a public health model, three types of strategies to prevent drug abuse can be discerned: primary, secondary and tertiary prevention. Primary prevention programs (anticipation and prevention of the occurrence of drug abuse) have mostly been directed to elementary grade school children in general. As knowledge about genetic predisposition increases, early developmental periods are increasingly plastic, and substance abuse is now beginning at earlier ages. Prophylactic interventions need to focus on childhood high-risk groups. With respect to secondary prevention (aiming at the discontinuation of infrequent drug-use) the stage (or stepping-stone) hypothesis is currently being challenged. Continuation is mainly a function of the type of drug as well as social and personality factors. Progression to higher-rank drugs depends mainly on the intensity of prior drug use. Comorbid psychiatric diseases are increasingly recognized and tractable. As in primary prevention the focus of secondary prevention shifts from sociocultural influences to the individual at risk. Regarding tertiary prevention (preventing the retaking of substances after achieving abstinence), research evaluating programs for the treatment of abuse of alcohol and other drugs indicates a limited staying power. Recent insights in the psycho- and neurobiologies of addictive behavior and in the psychopharmacological properties of alcohol and other drugs provide clinicians with new pharmacological tools to prevent relapse.