Journal of Adolescence Journal of Adolescence 31 (2008) 93–105 Determinants of adolescents’ active defending and passive bystanding behavior in bullying Gianluca Gini à , Paolo Albiero, Beatrice Benelli, Gianmarco Altoe` Department of Developmental and Social Psychology, University of Padua, via Venezia, 8, 35131 Padova, Italy Abstract The literature on participant roles in bullying lacks empirical studies that seek to explain what differentiates defenders from outsiders (or passive bystanders). The present study tested a conceptual model in which two personal characteristics of early adolescent students (empathy and perceived social self- efficacy) were considered as possible determinants of their participant behavior in bullying episodes. A total of 294 Italian early adolescents (mean age ¼ 13.3 years, range: 12–14) participated in the study. The structural equation modeling showed that high levels of empathic responsiveness were positively associated with both active defending and passive bystanding behavior, as assessed through peer nominations. In contrast, high levels of social self-efficacy were associated with helping behavior, whereas low levels of social self-efficacy were associated with passive bystanding behavior. Results are discussed in terms of theoretical and practical implications for researchers and educational practitioners. r 2007 The Association for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved. Bullying is a common problem faced by children and adolescents at school throughout the world (e.g., Forero, McLellan, Rissel, & Bauman, 1999; Pepler et al., 2006; Rigby & Slee, 1993; Smith et al., 1999, for a review). It has been defined as repeated aggressive actions aimed at causing physical or psychological harm or discomfort to one or more students who are weaker and unable to defend themselves (Olweus, 1993; Rigby, 1996; Smith & Sharp, 1994). Bullying may involve physical abuse, ARTICLE IN PRESS www.elsevier.com/locate/jado 0140-1971/$30.00 r 2007 The Association for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.adolescence.2007.05.002 à Corresponding author. Tel.: +39 49 827 6398; fax: +39 49 827 6511. E-mail address: gianluca.gini@unipd.it (G. Gini).