Nurse practitioners have evolved into a large and flexible workforce. Far too often, nurse practitioner and physician professional organizations do not work together but rather expend considerable effort jousting in policy arenas. Turf battles interfere with joint advocacy for needed health system change and delay development of interdisciplinary teams that could help patients. A combined, consistent effort is urgently needed for studying, training, and deploying a collaborative, integrated workforce aimed at improving the health care system of tomorrow. The country can ill afford doctors and nurses who ignore one another’s capabilities and fail to maximize each other’s contributions cost-effectively.