This chapter looks at why, when, who and where people move from one geographic region to another and the problems they have in adjustment. Asylum seekers, business people, students, volunteers, missionaries and new settlers become permanent or temporary sojourning expatriates and face particular problems. The chapter attempts to define the concept of “culture shock” and considers how it is measured. One of the more interesting ideas that emerge from this literature is the U and W curve hypothesis, which looks at a new settler’s adaptation over time. Whilst there is a considerable literature on foreign students, the chapter also looks at business people moving and working abroad. The costs of sending people abroad for a working sojourn can be very high and organizations are eager to ensure that their staff adapt and function well. Hence their attempts to select and support those who themselves choose and the organization chooses to send abroad. As a result there is a growing literature on the individual and social factors that seem to best predict successful adaptation while working abroad. The chapter also briefly considers the literature on cultural differences, which seeks to categorise countries on a limited number of psychological concepts (power-distance, uncertainty avoidance), so providing a “behavioural map” of the world that is useful in making predictions in how people may experience misunderstandings in travelling from one country to another. The final part of the chapter discusses theoretical models or frameworks that attempt to explain the nature of adaptation and culture shock, specifically how, when and why some individuals and groups appear to adapt less or more effectively and quickly. It also considers the theory behind and the efficacy of various methods that have been proposed to reduce stress among culture travellers.