Single-sex education refers most generally to education at the elementary, secondary, or postsecondary level in which males or females attend school exclusively with members of their own sex. This report deals primarily with single-sex education at the elementary and secondary levels. Research in the United States on the question of whether public single-sex education might be beneficial to males, females or a subset of either group (particularly disadvantaged youths) has been limited. However, because there has been a resurgence of single-sex schools in the public sector, it was deemed appropriate to conduct a systematic review of single-sex education research. The following are appended: (1) Quantitative Study Coding Guide; (2) Qualitative Study Coding Guide; (3) List of Quantitative Studies Excluded During Phase III; (4) Quantitative Coding Guide for All Studies; (5) Table of Study Outcomes for Boys; and (6) Table of Study Outcomes for Girls. (Contains 35 tables.)