This research summary identifies major factors affecting the validity of language assessments in bilingual students. The four factors include: (1) determining which language is dominant and in which language the child should be tested; (2) recognizing that bilingual children may use language in a way that is qualitatively different from that of monolingual children; (3) recognizing the influence of cultural differences and the local environment; and (4) overcoming the insufficiencies of existing diagnostic instruments. Literature-based recommendations for selecting a battery of language assessments are offered, and research needs are listed. A 35-item bibliography on assessing language disorders in bilingual students accompanies the research summary. (JDD)