The Technology Proficiency Self-Assessment (TPSA) questionnaire was administered to 978 elementary and middle school teachers from Mexico City, and 932 elementary and middle school teachers from the Dallas, Texas, metroplex in the USA, in order to examine self-efficacy similarities and differences for technology proficiency self-appraisals in a cross-cultural environment. Results indicate acceptable reliability and clear cross-cultural discriminant validity among the four subscales of the 20-item instrument. Texas teachers perceived themselves as more proficient in using e-mail and the World Wide Web than teachers from Mexico City, while the differences between the two groups were not large for self-ratings of integrated applications or teaching with technology. It is concluded that the TPSA is a useful measure for assessing level of proficiency in using technology among teachers from Texas and from Mexico City. It is also concluded that the measure is appropriate for studying differences between teachers from the two cultural contexts. Suggestions for future research include the need to control for certain variables such as large differences in technology access and a Hispanic ethnicity factor that appears to be present in the Texas sample. (Contains 4 figures and 5 tables.)