The authors point to the need for a scientific approach to the solutio
n of serious social problems which follow social, economic, and politi
cal changes. The approach of policy science together with Bandura's th
eory of social learning is recommended as a theoretical framework for
aimed interventions. The function of policy science is described in th
e context of liberal democracy and the significance of proximal and ma
nipulable variables is stressed in the social learning model. Differen
t types of intervention programs are presented together with possible
problems that may occur. The scientific approach to solution of social
problems is illustrated in five case studies of interventions in the
United States (social skills training related to prevention of sexuall
y transmitted diseases, life style modification focused on prevention
of cardiovascular diseases, prevention of smoking addiction in adolesc
ents, promoting employability in lower-income populations and improvin
g work ethics by ''workplace literacy programs''). The study concludes
by methodological observations concerning to ''policy science''.