The concepts of health valuing, multidimensional locus of control, and self-efficacy were conceptualized to represent related but distinct factors which are strongly associated with health-promoting behavior. The predictive power of this model was tested by following 75 smokers quitting through formal treatment programs and 75 smokers who quit by treating themselves for three months. Discriminant Function Analysis displayed significant predictive power from the model. Self-efficacy was the strongest predictor of abstinence versus relapse, but more accurately for self-treatment than for program treatment groups. Persons attributing greater power to health professionals were more likely to relapse. Health valuing displayed a diminished return curve. Results suggest that the enhancement of self-efficacy may be the most important task of treatment.