Supplemental Educational Services, mandated by NCLB as an option for students in low-performing Title I schools, has just completed its fourth implementation year, and a number of solid research reports on the Federal program are now available. This commentary reviews the political background to the out-of-school tutoring program, the for-profit companies and nonprofit organizations that are offering SES tutoring, the paucity of governmental oversight, and the generally low levels of student enrollment. Despite NCLB's emphasis on improving student achievement, the effects of SES on achievement remain difficult to evaluate.