This study examined the affective functioning of people with mild intellectual disabilities through examining salient variables that impact of people with disabilities who have been deinstitutioned. Its primary purpose was to extend previous research by incoporating adaptive behaviour, quality of life, in combination with multidimensional selfconcept, self-esteem and locus of control, in a longitudinal/comparison design. The study utilised a longitudinal/comparison group design. The results showed that the people who were deinstitutionalised benefited in some aspects of multi-dimensional self-concept, some subscales of quality of life, and three out of five factors of adaptive behaviour. The findings have important implications for current theory of the self-concept for people with intellectual disabilities, the provision of programmes and techniques to improve self-concept, hence the social integration of people who have been deinstitutionalised.