A replication of an original study of managerial assessment centers performed by Sackett and Dreher (1982) is presented. Their major finding, indicating that assessment centers lack key tenets of internal construct validity, was corroborated in this study of a hotel managers' assessment center. This hotel managers' assessment center is also found to be externally valid using criterion-related validity. The argument is posed that assessment centers, as standardized tests of complex behavioral traits, appear to be operating outside the bounds of normal test construction principles. Five key explanations for this paradox are offered to guide much needed future research in this area. Additionally, a description of commonly utilized assessment center activities is offered the reader.