Dropping out of high school is related to a number of negative outcomes. For example, the median income of persons ages 18 through 67 who had not completed high school was roughly $25, 000 in 2009. By comparison, the median income of persons ages 18 through 67 who completed their education with at least a high school credential, including a General Educational Development (GED) certificate, was approximately $43, 000. This book builds upon a series of National Center for Education Statistics (NCES) on high school dropout and completion rates that began in 1988. It examines trends in dropout and completion rates over the last nearly four decades (1972-2011), and explores the characteristics of high school dropouts and high school completers. Also discussed are the dropout prevention services and programs in public school districts.