Quantitative educational research with ethnic minorities has a long history, characterized by assumptions that are still operative, such as the assumption that the white male is the standard against which other groups should be compared. It has also been assumed that assessment instruments are applicable across all groups, and that sources of potential variance such as social class, language proficiency, or cultural orientation can be recognized but discarded. This paper challenges these assumptions and offers suggestions for improving quantitative research with ethnic minorities. New scholarship on ethnic minorities calls for a paradigm shift from the Eurocentric approach to an approach that values each ethnic group for its own sake. Problems in conducting research with ethnic groups center on (1) identifying, describing, and selecting a sample; (2) understanding heterogeneity within the group; and (3) language and cultural barriers. Methodologies to address these problem areas are outlined, focusing on the importance of adequate assessment instruments. (Contains 112 references.) (SLD)