Research in social psychology has extensively referenced and used Fishbein and Ajzen's theory of reasoned action to predict and understand motivational influences on behavior Recently Ajzen has proposed an extension of the theory by including perceptions of behavioral control as an additional predictor of intentions and behavior. The present research compared Ajzen's theory of planned behavior with the theory of reasoned action for 10 behaviors chosen to represent a range with respect to control over performing the behavior. he results indicate that inclusion of perceived behavioral control enhances the prediction of behavioral intention and behavior Consistent with the theory of planned behavior, the effects of perceived behavioral control on a target behavior are most vivid when the behavior presents some problem with respect to control.