Reviewed current conceptualizations of how health behavior and health status are linked. Although many health providers assume a near perfect relationship between health behavior and health status, empirical verification of this assumption has been difficult. For many diseases, the link between health behavior and health status is weak, nonexistent, or untested. Problems associated with the definition, conceptualization, and measurement of both health behavior and health status are discussed. The impact of treatment effectiveness (i.e., inert, weak, and strong treatments; treatments with linear versus nonlinear health-behavior relationships; and the effect of under- and overtreatment) on health behavior and health status linkages is illustrated.