The overall number of undergraduates at U.S. colleges and universities has increased dramatically over the past 20 years, with growth fueled almost exclusively by an influx of students from low-income families and students of color. But these changes are not occurring uniformly across the postsecondary landscape. This report shows that the rise of poor and minority undergraduates has been most pronounced in public two-year colleges and the least selective four-year colleges and universities, according to the Pew Research Center analysis of National Center for Education Statistics data.