1 British Journal of Social Psychology (2011) C  2011 The British Psychological Society The British Psychological Society www.wileyonlinelibrary.com Socially rejected while cognitively successful? The impact of minority dissent on groups’ cognitive complexity Petru Lucian Curs ¸eu 1 ∗ , Sandra G. L. Schruijer 2 and Smaranda Boros ¸ 1 1 Department of Organisation Studies, Tilburg University, The Netherlands 2 Utrecht School of Governance, Utrecht University, The Netherlands The impact of minority dissent on group-level outcomes is explained in the current literature by two opposing mechanisms: first, through cognitive gains due to a profound change induced by minority members in the individual cognitions of the majority members, and second, through socio-affective process losses due to social rejection and relationship conflict. Groups are most effective in information processing if they succeed in solving this opposition and reduce the negative impact of process losses. The present study addresses this opposition using an experimental design in which we crossed minority dissent (presence vs. absence of minority dissent) with change in membership (groups with vs. groups without change in membership) to determine which condition leads to the highest group cognitive complexity. Our results show that groups with a history of dissent and where the deviant left the group have the highest cognitive complexity, followed by groups that experienced dissent and where no change in group membership took place. The groups without a history of dissent have the lowest cognitive complexity. Considerable empirical evidence shows that minority influence fosters divergent think- ing and innovation in groups (De Dreu & West, 2001; Martin & Hewstone, 2003; Van Dyne & Saavedra, 1996) and can induce attitude change (Martin, Hewstone, & Martin, 2008). Although minority dissent was initially explored as a group process, most of the empirical evidence on the effects of minority dissent comes from a non-interaction paradigm (Martin & Hewstone, 2008; Smith, 2008). The literature on minority dissent mostly focuses on how minority dissent impacts on the cognitive dynamics of individual members (Smith, 2008), while there is little emphasis on the impact of minority dissent on global group dynamics (Choi & Levine, 2004; De Dreu, 2002) or on group cognition as an emergent group-level phenomenon. ∗ Correspondence should be addressed to Petru Lucian Curs ¸eu, Department of Organisation Studies, Tilburg University, Room P 1.161, Warandelaan 2, PO Box 90153, 5000 LE Tilburg, The Netherlands (e-mail: P.L.Curseu@uvt.nl). DOI:10.1111/j.2044-8309.2011.02023.x