This study is an effort to assess whether the concept of 'migration personality' applies in the context of Eastern Nigerian urban dwellers. Sickness and health care behaviour is compared between two groups--migrant urban households living in Uyo and Calabar and non-migrant rural households living in Ediene and Ibiono. The respondents' conceptions and perceptions of illness, disease and health as well as the medical services frequently used are analysed. The findings tend to confirm the existence of marked differences in disease beliefs and related health care behaviour in the two groups. These differences are crystallized along residency, socio-economic, age and income characteristics. The implication of the study is that even though it is not possible meanwhile to determine whether migration is an independent or intervening variable, or one of several other and inter-related variables, the fact that rural-urban migrants are so prone to modern medical practices, raises the desirability of using them as a target population for primary acceptance of modern medical programmes such as those concerning family planning, child nutrition and health.