Migration, whatever its cause or purpose, can place the individual under considerable stress. However, the process can be made more manageable and less traumatic by factors such as adequate preparation and social support, along with acceptance by the new culture. Whether individuals travel alone or with family, how the new country welcomes them, their legal status and economic factors all play a role in their adjustment to migration.

People moving within the same culture, for example those moving from rural hamlets to large cities, can also experience stress and feelings of alienation. The resulting changes in environment and social support can act as pathogens and the stress (following the stress diathesis model) can increase the likelihood of mental illness. The ideological commitments of individuals to the migration as well as their personality traits need to be understood (see Chapter 2, this volume). Coupled with personality traits are beliefs and attitudes related to the individuals’ own culture and their individual aspirations and role performance.

Personality factors lead to a number of stress-related illnesses. Eysenck (1990) noted that there is sufficient evidence to show that personality factors and stress can lead to feelings of helplessness and hopelessness and finally to depression. It has been argued that schizotypal personality disorder is associated with migration and subsequent psychosis, but no similar model has been identified for depression in immigrants. It is possible that some personality types are more vulnerable to dealing poorly with loss, and in such individuals it may produce depression.