Bilingualism profoundly impacts psychiatric diagnosis and psychotherapy because language is the primary tool of both processes. This article reviews the contemporary research literature in the area of mental health assessment and treatment of bilingual individuals in the United States. It was found that bilingualism introduces special concerns to clinicians independent of language of assessment and regardless of whether a translator is used in the interview process. Bilingualism may interfere with clinician and patient knowledge and rapport, leading to qualitative as well as quantitative differences in assessment and treatment. Nevertheless, an understanding of the dynamics of bilingualism provides opportunities for practitioners to enhance the mental health care of bilingual patients.

The superior control of cognitive processing demonstrated by children in the early stages of additive bilingualism may enhance symbolic reasoning abilities. The developmental interdependence of LI and L2 may allow additive‐bilingual children to maintain normal native‐language development. This study examined the development of a Grade 2 additive‐bilingual (Spanish‐immersion) program class as compared to a monolingual classroom on measures of nonverbal problem‐solving and native‐language development. Theprogramwas the independent variable in two comparisons. In the first comparison, nonverbal problem‐solving was the dependent variable, as measured by Raven's (1977) Coloured Progressive Matrices (CPM). As hypoth‐esized, a repeated measures ANCOVA of the results of fall and spring administrations of the CPM indicated significant differences in favor of the Spanish‐immersion group, F(1, 35)=5.85, p=.O2. In the second comparison, native‐language development was the dependent variable as measured by the Peabody Picture Vocabulary Test‐R (PPVT‐R). A parametric independent