The JERASS special project group "Internationalization of Social Studies Research Methodology" has invited leading researchers from the United States to the international conferences on social studies research trends and issues. The purpose of this issue is to discuss the results of a series of conferences as an interim report. This issue includes three written by US researchers and three short commentaries written by Japanese researchers. The themes of the keynote speechees that the US researchers delivered are as follows: (1) Stephen J. Thornton, Enhancing Curricular-Instructional Gatekeeping in Social Studies, on March 3, 2012 at Kyoto: Ritumeikan University. (2) Bruce A. VanSledright, Ways of Making Sense: Researching Students' Historical Thinking and Understanding, on January 22, 2012 at Osaka: CIC Osaka (3) Carolyn O'Mahony, Researching Planning in Elementary Social Studies in the Digital Age: Exploring the Potential of Lesson Study to Energize Teachers and Revitalize a Field, on August 28, 2011 at Osaka: Osaka Kyoiku University The group coordinator of each conference is requested to outline these US researchers' speeches and articles with focuses on the current trends and issues of research in the United States. The summaries of the invited US researchers speeches at the conferences are followings. (1) A big picture of social studies is not advocated. The US researchers seem not to draw a "macro and grand design," which guides theory and practice into school education. As a more multicultural, fragmented society emerges, it would be difficult to generaliaze the comprehensive concept on social studies. (2) The themes of teacher/teaching and learner/learning are their main focuses. As opposed to the trend of educational standardization, these US researchers attempt to describe the various perspectives of learners, as well as the adjustable but independent decision makings and autonomous communities of teachers, in terms of historical thinking, gatekeeping, and lesson study. (3) Some researchers underwent a cognitive revolution in the 80s as graduate students. The movement introduced them to the reams of qualitative research for analyzing the human subject of a social studies class with a "micro but thick description." According to a recent survey, Japanese researchers show tendencies entirely different from those in the United States. They are likely to write a paper that draws a grand design of social studies together with the development of some types of modules to improve classroom teachers' teaching strategies. The readers of this issue could find the differences of the research methodological trends between Japan and the United States through reading the US researchers' articles.