Thanh V Tran , PhD, is associate professor ; and Leon F. Williams , PhD, is associate professor ; Graduate School of Social Work , Boston College, 216 McGuinn Hall, Chestnut Hill, MA 02161. The data used in this publication were made available by the Interuniversity Consortium for Political and Social Research. The data for the National Survey of Hispanic Elderly People were originally collected by Karen Davis and the Commonwealth Fund. The authors bear all responsibility for the analysis and interpretations presented here and thank the anonymous reviewers for their comments. Social people long titioners ferently scientists recognized across (Palmore, have conversely doing cultures the 1983). cross-cultural need behave been Human to understand cognizant similarly services research or of prachave how difthe long recognized the need to understand how people across cultures behave similarly or differently (Palmore, 1983). Human services practit on h v conve sely een co zant f t e need to provide different treatments or services to meet the needs of clients across ethnic populations (Henderson, 1989; Lum, 1992). In this article, we focus on an important methodological issue of cross-cultural research: the effect of the language of interview on psychometric properties of critical research measures. Several studies of Hispanic populations have been concerned with the uniformity of data (Trevino, 1988), the comparative translation of research instruments (Berkanovic, 1980), and the effect of the language used in an interview on outcome variables (Kirkman-Liff & Mondragon, 1991). However, no previous study has examined whether language of interview affects the psychometric properties of outcome variables such as psychological well-being. Traditionally, investigators have used translation as a method to achieve comparability in cross-cultural research. In addition, non-English-speaking respondents have often been given the choice of being interviewed in English or in their native language. Investigators tend to assume that good translation guarantees cross-cultural comparability of research methods across ethnic groups. This belief may mask true substantive similarities or differences between ethnic groups. An examination of the effect of language of interview on the measurement properties of psychological variables should indicate not only whether the translation truly achieves cross-cultural comparability but also whether it, in fact, confounds the comparability of research instruments. This research assumes that the language of the interview, whether conducted directly or indirectly, has an influence on the reliability and validity of research instruments.