Drury: Reactions to London bombings 66 International Journal of Mass Emergencies and Disasters March 2009, Vol. 27, No. 1, pp. 66–95. The Nature of Collective Resilience: Survivor Reactions to the 2005 London Bombings John Drury University of Sussex, UK Chris Cocking London Metropolitan University, UK Steve Reicher University of St Andrews, UK Email: j.drury@sussex.ac.uk Accounts from over 90 survivors and 56 witnesses of the 2005 London bombings were analysed to determine the relative prevalence of mass behaviors associated with either psychosocial vulnerability (e.g. ‘selfishness’, mass panic) or collective resilience (e.g. help, unity). ‘Selfish’ behaviors were found to be rare; mutual helping was more common. There is evidence for (a) a perceived continued danger of death after the explosions; (b) a sense of unity amongst at least some survivors, arising from this perceived danger; (c) a link between this sense of unity and helping; and (d) risk-taking to help strangers. We suggest a novel explanation for this evidence of ‘collective resilience’, based on self-categorization theory, according to which common fate entails a redefinition of self (from ‘me’ to ‘us’) and hence enhanced concern for others in the crowd. Keywords: London bombings, resilience, panic, self-categorization Introduction On July 7th 2005, a series of coordinated terrorist bomb blasts hit London’s public transport system during the morning rush hour. The London bombings saw the largest mass casualty count in the UK since World War II (Aylwin et al. 2006). The present paper presents an analysis of survivors’ behaviors and experiences as collected in contemporaneous newspaper data, personal accounts, and interviews. Patterns in each of these datasets are analysed quantitatively and qualitatively in order to evaluate two