Much of the potential for reducing cancer mortality is dependent on the adoption of new behavioral patterns. Such changes demand application of the behavioral-social sciences. A shift from univariate reductionist models of causation toward multivariate systems models is needed. Decisions (and behavior) are the focus of much of the behavioral-social sciences. Determinants of decisions are delimited by controlling systems. Health care is only one of many possible influences on controlling systems, and its influence is only marginal for the behavior of the general public. Thus, community interventions that address multiple determinants within controlling systems are needed to influence most behaviors. Belief saliency hierarchies appear to psychologically mediate controlling systems. Changes in these saliency hierarchies lead to changes in behaviors. Person-valued beliefs, socialvalued beliefs, and feasibility beliefs serve as the informational basis for the hierarchies. Needs activation is a primary means by which hierarchies shift. Changing environmental cues and signals also impart such shifts. Experience, persuasive communication, and value extracted from the environment also change hierarchies. Needs activation, community presence, persuasive communication, facilitation, inhibition, and experiencebased interventions are discussed for tobacco use control, dietary change, and breast and cervical cancer screening behavior. Emphasis is given to how the health care system can become a part of the controlling system that influences community behavior. Issues concerning successful implementation of community education programs are raised. Cancer 1993; 721125-31.