This thesis presents a critical literature review and reports on the findings of three empirical studies, examining the relationship between life events and psychological problems in people with intellectual disabilities. An introduction is provided in Chapter 1. The critical review (Chapter 2) describes the current evidence base in relation to a critical framework that aims to establish life event exposure as a causal risk factor for psychological problems. Chapter 3 presents the results of a longitudinal study, using data from proxy informants, and begins to address the need for further longitudinal data in establishing life events as a risk factor. Chapter 4 presents the results of a self-report study of life events, psychological problems and social support, intended to establish whether valid data on life events could be obtained using self-report interviews with people with intellectual disabilities The putative role of social support as a moderator in the relationship between life events and psychological problems is also examined. Chapter 5 presents the results of a longitudinal study of life events in children with intellectual disabilities, which begins to address the need for further studies of life events in children with intellectual disabilities, and in particular, the need for longitudinal evidence. Chapter 6 draws together a number of conclusions from the present work, and provides a methodological critique. The findings in the reported studies are broadly consistent with published reports on life events in people with intellectual disabilities. Life events can be said to be a risk factor for psychological problems in adults with intellectual disabilities, though insufficient data has yet been gatheredt o establishl ife events as a causarl isk factor. In children with intellectual disabilities, the data suggest a number of specific relationships between certain types of life event and psychological disorder, rather than global associations.