A conceptual analysis of basic notions of addictiology, i.e., Euphoria, Ecstasy, Inebriation, Abuse, Dependence, and Addiction was presented. Three different forms of dependence were distinguished: purely psychic, psycho-physiological, and purely somatic dependence. Two kinds of addiction were differentiated, i.e. appetitive and deprivative addiction. The conceptual requirements of addiction were discussed. Keeping these in mind some ethical problems of drug therapy and psychotherapy were explained. Criteria for the assessment of therapeutic approaches are suggested: effectiveness, side effects, economic, ethic, and esthetic valuation.