This report examines what is known about enrollment, discipline, and support staff in alternative schools, among other objectives. The Government Accountability Office (GAO) analyzed data on alternative schools for school years 2013-14 and 2015-16 from Education's Civil Rights Data Collection (most recent years available); visited selected school districts and alternative schools in Florida, Illinois, and Texas, selected for a mix of types (regular alternative, charter, and juvenile justice) and focuses (disciplinary or academic) of alternative schools; and interviewed federal officials. Findings showed that certain groups of students are overrepresented at alternative schools--public schools with a disciplinary or academic focus that serve students who have been expelled or suspended from school, or are at risk of educational failure--compared to their enrollment at nonalternative schools. Overall enrollment and discipline of students at these schools dropped between school years 2013-14 and 2015-16, according to GAO's analysis of Department of Education (Education) data. Declines in White and Hispanic student enrollment accounted for most of the drop. Some groups, such as Black boys and boys with disabilities, were overrepresented in alternative schools, particularly those with a discipline focus, compared to their enrollment at nonalternative schools. While overall discipline dropped for students at alternative schools, school arrests and referrals to law enforcement went up by 33 and 15 percent, respectively, for Black boys and girls between school years 2013-14 and 2015-16.