Migration is known to be associated with poor health outcomes for certain marginalised and socially disadvantaged populations. This paper reviews a number of reasons why residential mobility in the 'host' country may be associated with poor mental health for refugee populations and reports on a qualitative study of Somalis living in London, UK, and their beliefs about the relationship between residential mobility, poor health and health service use. Two discussion groups were undertaken with 13 Somali professionals and four groups with 21 lay Somalis in East and South London, UK. Lay Somalis did not wish to move accommodation but felt they were forced to move. Some Somali professionals believed that the nomadic history of Somalis made them more likely to elect to move in order to escape problems of living, but this was not supported by the lay group. Frequent geographical movements were seen as stressful and undesirable, disrupted family life and child development and were detrimental to well being. Residential mobility was also perceived to interfere with health care receipt and therefore should be more comprehensively assessed in larger quantitative studies.