Surveys and a brief-interval longitudinal design were employed to investigate the relationships between selected proactive leader influence behaviors (PLIBs) and followers' commitment to their leaders. Selected elements of followers' implicit leadership theories (ILTs) were expected to moderate the PLIBs – commitment relationships. Hypotheses were generated and tested in order to determine the extent to which (1) PLIBs constituted group-level phenomena and (2) PLIBs and ILTs were related to follower commitment. Empirical evidence did not support treating PLIBs as group-level variables. While PLIBs were related to commitment, hypotheses specifying ILT dimensions as moderators of the PLIB – commitment relationships were not supported. / Ph. D.