ABSTRACT Several theorists have suggested that impulsivity can be understood as a joint function of the behavioral approach (BAS) and behavioral inhibition systems (BIS). After resolving questions concerning the measurement of impulsivity and BAS, this study examined the relationships among risky health behaviors, impulsivity, BIS, and BAS. Utilizing a sample of undergraduates (N=904), a structural model was tested in which BAS and BIS predicted impulsivity, which, in turn, predicted risky behavior. Fit indices were acceptable, but not good. A modified version of the model showed a statistically significant negative relationship between BAS and risky behaviors. However, the fit indices were not unequivocally supportive of the need to include that path. Overall, the data suggest that impulsivity is the joint result of countervailing motivational forces and that it partially or fully mediates the influence of BIS and BAS on risky health behavior.