The health of populations residing on either side of the United States–Mexican border has public policy implications for both border communities. A study of barriers to prenatal care for residents of the San Diego, California–Tijuana. Mexico region was conducted. The study was designed specifically to address the availability of health services for women who crossed the border in either direction. This article reports the methodology used in the construction and validation of a dual-language (as opposed to a Spanish language form) survey instrument that was developed for the study. Particular attention is given to the methodology used for language translation to ensure that it would reflect the idiomatic diversity of the multicultural population.