Current practices for assessment of language in bilingual students frequently involve the use of tests translated from English to the target language or tests designed for, and normed on, monolingual people. This Digest explains why these common approaches are not well suited for a bilingual population and provides guidance regarding more suitable approaches. There are many problems with test translation. Tests translated from one language to another do not retain their psychometric properties, and issues of equivalence of both vocabulary and grammar surface. Bilingual school children usually are circumstantial bilinguals, and their vocabularies in the different languages may reflect the different circumstances in which the vocabulary is used. Language tests can be improved if test developers: (1) ensure that concepts and linguistic features are appropriately represented for each language; (2) use conceptual scoring systems to eliminate underestimation of ability; (3) select an appropriate mix of item types to gain the maximal amount of information about language ability in each language; and (4) consider the frequency of occurrence of the words. (Contains 11 references.) (SLD)