The idea that online learning might revolutionize higher education, lowering the cost of high-quality learning opportunities for students with limited access to traditional higher education, follows similar hopes for earlier technologies, including radio and television. If such a revolution is to come, it is still far from a reality. Strong evidence indicates that students with weak academic backgrounds and other risk factors struggle most in fully online courses, creating larger socioeconomic gaps in outcomes than those in traditional classroom environments. The central problem appears to be the lack of adequate personal interaction between students and instructors, as well as among students. Hybrid learning models do not exhibit the same problems and there is potential for online learning to develop strategies for overcoming these difficulties. Meanwhile, narrowing gaps in educational opportunities and outcomes requires considerable skilled human interaction.