Previous research on expatriation has focused principally on managers in multi-national corporations. However, there is an acknowledged need to disaggregate the expatriate population in order to recognise the different contexts in which expatriation takes place. This thesis focuses on expatriation within the context of international development, evaluating the process and outcome of sociocultural adjustment in individual development workers. Development workers are an important type of expatriate to study. Their ability to adjust effectively to host cultures is increasingly important as NGOs face growing competition for funds alongside greater calls for accountability and increased demand for their services. Moreover, development work is theoretically challenging as a result of close contact with host nationals, a greater degree of cultural distance between home and host cultures, and the witnessing of poverty and inequity. A mixed method approach was employed in this thesis. Semi-structured interviews were used to evaluate the sociocultural adjustment experiences of expatriate development workers together with reflections on the contribution of their sending organisations. A postal survey was subsequently used to examine recruitment, selection and cross-cultural training practices in a broader sample of UK-based NGOs. This thesis makes its contribution by evaluating sociocultural adjustment in an under-researched expatriation context that is argued to be especially challenging both for the sending organisations and the individual expatriates. The findings identify a number of specific challenges, and provide a rich insight into the way in which these combine to influence the sociocultural adjustment of expatriate development workers and the adjustment outcomes that they achieve. Despite being a challenging context, the development workers in this study had all reached positive adjustment outcomes. The role of sending organisations was also examined, which indicated that recruitment, selection and cross-cultural training practices were shaped by pragmatic considerations. This was evidenced by an emphasis on recruitment sources and selection criteria that sought to identify qualified and experienced individuals with minimal training needs. Cross-cultural training focused on the provision of project and organisational inductions, supporting this interpretation. The findings led to the proposal of a model of sociocultural adjustment in expatriate development workers. The model emphasises the need to balance the use of other expatriates as a support mechanism with the effect of this on the individual’s relationship with host nationals. The model also identifies several factors that can simultaneously create tensions between expatriates and host nationals whilst driving the expatriate to seek support from other expatriates.