A study investigated the effects of U.S. mass media on three dimensions of Thai society: lifestyles, social problems, and value conflict. A total of 100 two-part questionnaires were distributed to Thai students at southwestern public universities in the United States. Forty males and 28 females, whose lengths of stay in the United States varied from 2 months to 15 years, returned usable questionnaires. Subjects were asked to indicate their degree of concern for changes in the three dimensions, as well as to rank the five types of mass media--radio, TV, film, newspapers and magazines, and videocassettes--according to their effects on Thai society. Results indicated that respondents believe U.S. mass media has affected Thailand's lifestyles most, and had lessen effects on social problems and value conflict. Results also showed that the longer the respondents stayed in the United States, the less they perceived the impact of U.S. mass media, and that females were more concerned about the effects of mass media than males. Finally, both sexes ranked television as the most important media, but males believed that videocassettes ranked second in importance, while females ranked them as least important. Although the study should be replicated with respondents who are not liberal Bangkok residents (as most in this study were), it does suggest that U.S. mass media is having a sizeable impact on Thai society, and almost every facet of Thai society is currently integrating Western values. (Five tables, four pages of references, and copies of the questionnaire in English and Thai are included.) (JC)