"... intentions are our best single predictors of whether one will or will not perform a given behavior... according to a reasoned action approach, there are three primary determinants of intention: the attitude toward performing the behavior in question, normative influence or the amount of social pressure one feels vis-a-vis performing the behavior, and one's self-efficacy with respect to performing the behavior. The relative importance of these three psychological variables as determinants of intention will vary as a function of both the behavior and the population being considered. Thus, before developing interventions to change intentions, it is important to first determine the degree to which that intention is under attitudinal, normative, or self-efficacy control in the population in question. It should be clear that very different interventions are needed for attitudinally controlled behaviors than for behaviors that are under normative influence or are strongly related to feelings of self-efficacy. Clearly, one size does not fit all, and interventions that are successful in one culture or population may be a complete failure in another."*
-- In Memoriam: Martin Fishbein, 1936-2009 
*from Fishbein, M. (2009). An integrative model for behavioral prediction and its application to health promotion. In R. J. DiClemente, R. A. Crosby, & M. Kegler (Eds.), Emerging Theories in Health Promotion Practice and Research, 2nd Ed. (215-234). Jossey-Bass: San Francisco, CA.
Photo credit: http://www.asc.upenn.edu/Martin-Fishbein/