According to the "Internal-External Efficacy model", self-efficacy is an insufficient explanation for self-regulated behavior because it ignores the influence of external resources. Applying this theory of motivation to the prediction of creative performance, the extent to which means efficacy or the belief in the utility of external resources predicted independent assessments of creativity was tested. In Study 1, student webmasters' (N =124) means efficacy predicted subject matter expert's ratings of creativity of student organization homepages. In Study 2, employees' (N = 128) means efficacy predicted individual supervisory ratings of creative performance. In addition, means efficacy enhanced the positive relationship between creative self-efficacy and supervisors' ratings of creative performance. Implications for enhancing creativity in the workplace are discussed.