After World War II, the United States decided to support much of its basic research through universities. That decision invigorated research with the energy, abilities, and fresh perspectives of students, while creating a fertile training ground for future researchers. Doctoral education in the U.S.--the education and training of Ph.D.s--became a combination of study and apprenticeship. As a result, doctoral students work with faculty mentors in teaching and research, in addition to their coursework. This enables them to acquire an understanding of teaching and research techniques, and by the end of their doctoral programs, they are required to demonstrate that they can do independent research that advances the frontiers of knowledge. This paper describes why federal support is important for doctoral students and discusses how they are supported.