This article supported the hypothesis that leaders' and members' attribution styles have interactive effects on members' perceptions of the quality of their leader-member relations. Across two samples, results revealed an interactive effect such that members' perceptions of poor leader-member relations were most accentuated when they were biased toward external and unstable attributions (i.e. optimistic attributions) for their negative outcomes, while their leaders were biased toward attributing negative outcomes to the internal and stable characteristics of the members (i.e. pessimistic attribution styles). In Study 2, results indicated that the members' perceptions of distributive and procedural justice mediated the interactive effects of leader pessimism and member optimism on relationship quality. © 2007 Elsevier Inc. All rights reserved.