What are the effects of revealing dimensions to candidates in an assessment centre? This question is addressed in two independent studies, using individual exercises. Results in Study 1 showed no difference in construct-related validity between a transparent (N = 99) and a non-transparent group of university students (N = 50), contrary to previous findings by Kleinmann, Kuptsch, and Köller (1996) and Kleinmann (1997), who used group exercises. Also, mean ratings did not alter, the exception being the dimension "Sensitivity", which increased slightly after the transparency treatment. Conversely, results in Study 2, which contained a sample of actual job applicants, showed a significant improvement in construct-related validity for the transparent group (N = 297) compared with the non-transparent group (N = 393). Again, mean ratings did not differ between these two groups. Implications of these findings for practice and suggestions for future research are discussed in this paper.