This edited volume contains the proceedings of a conference on the role of individual differences in instructed SLA held at Aoyama Gakuin University in 1999. It includes 11 studies as well as an introductory chapter written by the editors. The first two papers, by Yamashiro and McLaughlin and by Hiser, Croker, Kenudson, and Stribling, present multivariate statistical analyses to examine the interrelationship between motivation, second language (L2) proficiency, and other learner characteristics in Japanese student samples. Although both studies offer unique insights into the characteristics of their target population, the authors also call for methodological improvements that would go beyond the use of self-report questionnaires. Sharing a similar interest in improving motivation research methodology, another study by Hsiao explicitly sets out to test the construct validity of the most well known motivation test—Gardner's Attitude/Motivation Test Battery—in Taiwan, which is a very different learning environment from Canada, where the test was originally developed. Özek and Williams's paper is also of interest in this respect because in their study a questionnaire survey conducted in Turkey was complemented with qualitative interviews, thereby resulting in a particularly rich database.