The Clance Impostor Phenomenon Scale (CIPS; Clance, 1985) was compared to the newly developed Perceived Fraudulence Scale (Kolligian & Sternberg, 1991). The two scales were found to have high internal consistency and to correlate in a similar manner with other measures. Further, discriminant validity evidence for the Impostor Phenomenon (IP) was provided by comparing the CIPS to measures of depression, self-esteem, social anxiety, and self-monitoring. The IP was related to, but substantially discriminable from, these constructs. Finally, construct validity evidence for the CIPS was provided through principal components analysis that yielded three stable factors: Fake, Discount, and Luck.