This chapter describes collective trauma as an under-recognised but salient response to various types of massive traumas resulting from disasters and representing the negative impact on social processes at the collective level. It also describes the effect of collective trauma on migration and settlement in the host country and various interventions that can be used in such contexts. Disasters have an effect not only on individuals, but also on their family, ethnic group, community and wider society. The widespread problem of collective traumatisation and loss of communality following disasters is best approached through family and community level interventions. Although migrants with collective trauma may initially resist attempts at socialisation, it is worthwhile encouraging and organising supportive intra- and inter-group interactions. Self-help, supportive and other types of groups based on similar backgrounds, gender or goals are helpful in ameliorating the effects of collective trauma and re-establish trust, relationships and networks.