Culture shock is a polyphasic psycho-sociophenomenon, a reactive process stemming from the impact of a new culture upon those newcomers who attempt to merge with it. The violent removal from an "average expectable environment" and subsequent exposure to a new, relatively unpredictable, strange new environment, triggers off the process of culture shock. Mourning for the massive loss of loved objects—the abandoned culture—and its concomitant threats to the individual's identity constitute the common denominator of culture shock. Also, I have emphasized adaptive functions of mourning as prerequisites for a successful solution of culture shock. The sequential stages of the process of culture shock were described, from the initial mourning and the various threats to the newcomer's identity, the working through of mourning and the vicissitudes of identity, to final transformations and reintegration of the newcomer's identity.