This study tested five confirmatory factor analytic (CFA) models of the Positive Affect Negative Affect Schedule (PANAS) to provide validity evidence based on its internal structure. A sample of 223 club sport athletes indicated their emotions during the past week. Results revealed that an orthogonal two-factor CFA model, specifying error correlations according to Zevon and Tellegen's mood content categories, provided the best fit to our data. In addition, parameter estimates for this model suggest that PANAS scores are reliable and explain large proportions of item variance. Taken together with previous research, the findings further suggest that the PANAS may be a higher-order measure of affect and includes several consistently problematic items. The authors recommend that affect researchers attempt to improve the PANAS by (a) revising consistently problematic items, (b) adding new items to better capture mood content categories, and (c) providing additional internal structure validity evidence through a diagonally weighted least squares estimation of a second-order PANAS CFA model. (Contains 1 table and 1 figure.)