Teacher quality, however defined, is usually seen as the responsibility of schools of education. Rarely is it viewed as the responsibility of academic departments in the arts and sciences--that part of college or university where prospective teachers study the academic content they will draw on as teachers. Only recently has teacher quality come to be seen as a major responsibility of a state department of education and to be linked to student learning, traditionally the responsibility of the local school district. This essay sets forth the many ways in which a state department of education can enhance teacher quality and the supply of academically able teachers. I draw on my own experience in directing revisions of the major documents produced by the Massachusetts Department of Education from 1999 to 2003 and on several other major initiatives undertaken by the department to implement the education reform measures enacted and funded by the Massachusetts legislature in the 1990s. The chief documents that were the focus for my own work consisted of the preK-12 curriculum frameworks in all basic subjects, the regulations for licensing teachers and teacher-training programs, and the teacher tests required for licensure. The general goals of the department relating to teacher quality and supply have been to attract more high-achieving undergraduate majors, college graduates, and academically able midcareer changers to teaching as a career; to increase the academic qualifications of teachers completing approved training programs; and to increase the academic knowledge of the current teaching force. I first describe all the major ways in which the department sought to achieve these goals. I then report on the results of these initiatives based on available evidence, and I review what lessons the department has learned that may be useful for others. I conclude with a discussion of the possible effects of the accountability provisions of the No Child Left Behind legislation on state efforts to achieve these goals at a time of state and local budget constraints and with suggestions about ways to reconceptualize the institutional framework for teacher training in the United States. ["Can a State Department of Education Increase Teacher Quality? Lessons Learned in Massachusetts" was written with Lisa Haverty.] (Contains 6 tables and 25 notes.)