Use of competency models has exploded in recent years. Unfortunately, the empirical research to validate such systems is scarce. This study explores the relationship between Competency-based Performance Management Systems and sales performance to determine whether the use of these systems increases performance. Performance data from sales representatives in a medical products company were examined to determine changes in performance following the introduction of the Competency-based Performance Management System (N=64). Correlations with performance were obtained for each competency dimension to determine if any factors were highly correlated with performance and if state-factors were more positively correlated with performance than trait-factors (N=66). The study found no significant relationship between implementation of a Competency-based Performance Management System and sales performance. Also state-factors were not more positively correlated with sales performance than trait-factors.