The Doctor of Nursing Practice degree: lessons from the history of the professional doctorate in other health disciplines.

Despite the American Association of Colleges of Nursing's adoption of the Doctor of Nursing Practice (DNP) degree as the appropriate level of education for advanced practice, a number of controversies have persisted, including questions of timing, academic support, grandfathering, diffusion of nursing research, and economics. This article discusses the path to the professional doctorate in optometry, osteopathy, public health, pharmacy, physical therapy, audiology, chiropractic, and naturopathy. It reveals similar struggles to professionalism and the consensus drawn from doctoral development in these fields. It concludes with lessons for a path forward for the DNP.