This article describes and analyzes the unique challenges that face psychiatrists and other mental health professionals serving a multicultural population in a limited geographic setting, based on the author's experiences working as a psychiatrist on a mobile crisis unit from 1984 through 1991 on the Lower East Side of Manhattan.

Of special importance, the paper presents and provides support for the « interaction hypothesis », which proposes that sociocultural background factors interact with mental disorders to produce dissimilar behavioral expressions of the same disorder among members of different ethnic groups.

Concern is voiced that mental health professionals, in order to provide effective treatment in multicultural settings, need to understand and accept each ethnic group's idiosyncracies, identity, and background.