Interpretations of studies which show a correlation between migration and mental illness generally focus on sociocultural variables while giving scant attention to determinants of cognitive-personality orientations. This article examines childhood socialization practices as a key variable for comparing points of psychological stress between the traditional rural culture and the post-industrial urban culture. The hypothesis that harsh and restrictive childhood socialization practices foster the development of a cognitive-personality orientation which increases the likelihood of maladaptive responses to culture change is illustrated by anthropological and psychological data obtained from Sicilians living in Sicily, the U.S.A. and Australia. Suggestions are given for minimizing the mental health risks involved during the critical transition period following migration.