As physician assistant (PA) programs developed in the 1960s, curriculum models emerged around the central themes of physician-dependent practice and competency-based education. By 2007, there were 136 accredited programs in the United States, with 108 (79%) offering a master-degree curriculum. PA program preclinical and clinical curricula are typically evenly divided in length, and the typical U.S. PA program has a full-time attendance curriculum of 26.5 continuous months. In academic year 2005-2006, the typical PA student was a 27-year-old white woman with a 3.4 overall grade point average and 29 months of prior health care experience who matriculated with a baccalaureate degree into a master-degree PA program. In the 2005 application cycle, the number of applicants per available seat was 2.25 for both allopathic medical schools and PA programs. The transition to a predominately master-degree curriculum resulted in new challenges for PA faculty development, and the number of PA educators with terminal academic degrees continues to lag behind the educational needs of training programs. The topic of PA specialty training and recognition remains controversial. Although the PA profession has prospered since inception, concerns exist regarding workforce issues such as the appropriate balance of autonomy and supervision, role delineation, and the continuing trend toward specialization. The omission or inaccurate classification of PAs within U.S. health care access and workforce literature projects an incomplete picture, and it is important to consider the contributions PAs have made and will continue to make in addressing the nation's health care needs.