The authors used longitudinal multisource field data to examine core aspects of the adaptive self-regulation model (A. S. Tsui & S. J. Asliford, 1994) in terms of linkages between self-monitoring, discrepancy in manager match-to-position, 5 measures of leadership, and manager performance. At Time 1, 64 superiors of focal managers rated the managers' matches to their positions within the organization; at Time 3, they rated the managers' performance. At Time 2, the 64 focal managers completed a measure of self-monitoring, and 192 subordinates rated the focal managers' leadership behaviors. Results of partial least squares analysis revealed that discrepancy in manager match-to-position was associated with reductions in laissez faire and passive management-by-exception behaviors and increases in transformational leadership behavior. Self-monitoring was positively associated with all 5 leadership behaviors. Performance was related positively to transformational leadership behavior and negatively to passi ve management-by-exception and contingent-reward behaviors Key words: adaptive self-regulation, discrepancy detection, discrepancy reduction, leadership behaviors, managers, match-to-position, performance appraisal, self-monitoring, subordinates, superiors, SEVERAL THEORIES OF SELF-REGULATION suggest that managers who readily adapt to a variety of organizational requirements and contexts can maximize their effectiveness (Atwater & Yammarino, 1997; Carver & Scheier, 1985; [...]