During the last two decades, estimates from the U.S. Census Bureau have suggested that the U.S. high school completion rate was steadily rising and nearing 90 percent. In the last few years, however, estimates from independent researchers have contradicted this rosy picture and found much lower completion rates ranging from 66.1 percent to 74.4 percent. In this article, researcher Paul E. Barton describes the results of his own analysis, which confirmed the other independent estimates. He also points out that the economic prospects of these dropouts have become more grim. Barton cites a General Accounting Office report that identified four factors correlated with low high school completion rates: coming from low-income and single-parent families, getting low grades in school, being absent frequently, and changing schools. He describes a number of successful programs and models that support students at risk of dropping out, and calls on school leaders to use this knowledge to guide reform efforts.