"U.S. Performance on the 2015 TIMSS Advanced Mathematics and Physics Assessments: A Closer Look" expands upon the results described in NCES' [National Center for Education Statistics'] initial "Highlights" report on TIMSS Advanced. This new report provides in-depth analyses that (1) examine the demographics, school characteristics, and coursetaking patterns of the small subset of U.S. 12th-graders taking the TIMSS Advanced assessments; (2) describe the extent to which the topics assessed in the study were covered in the curricula of the advanced mathematics and physics courses taken by U.S students; (3) provide detailed performance data within content domains for student subgroups and overall; and (4) illustrate student performance with example items. This report uses data from the 2015 Trends in International Mathematics and Science Study Advanced (TIMSS Advanced), an international assessment that measures advanced mathematics and physics achievement in the final year of secondary school. TIMSS Advanced is sponsored by the International Association for the Evaluation of Educational Achievement (IEA) and conducted in the United States by NCES.