Sociometric studies have shown that some aggressive boys are popular, perceived as popular or cool, dominant, and central in the peer group (Estell, Cairns, Farmer, & Cairns, 2002; Milich & Landau, 1984; Prinstein & Cillessen, 2003; Rodkin, Farmer, Pearl, & Van Acker, 2006). This is not predicted by social information processing (SIP) models which see aggression as socially incompetent, resulting from distorted understanding of the social world (e.g. Crick & Dodge, 1994). However, sociologists of childhood have argued that some aggressive boys are popular because they use aggression to gain status and dominance, to undermine those of lower status, and to achieve hegemonic masculinity (Adler & Adler, 1998; Ferguson, 2000; Renold, 2007). This study aims to connect psychological and sociological literatures, asking whether social processes of status formation contribute to the link between popularity and aggression identified sociometrically. The paper describes case studies of three boys, aged between 8 and 10 years, attending a London primary school. Sociometric data on liking, disliking, and aggression are combined with ethnographic and interview data for each case study. The data show that one way in which aggression aids popularity and dominance is through boys' strategic use of aggression to enforce decisions about inclusion and exclusion in desirable activities. It can be difficult for individual boys to achieve acceptance without resorting to aggression. The data provide support for sociological explanations of aggression in terms of status and inclusion, and challenge the SIP claim that aggressive children are socially incompetent and biased.