Not long ago, I attended a meeting on the future of primary care. Most of the physicians in the room knew one another, so the discussion, while serious, remained relaxed. Toward the end of the hour, one of the physicians who had been mostly silent cleared his throat and raised his hand to speak. The other physicians smiled in acknowledgment as their colleague stood up. "Nurse practitioners," he said. "Maybe we need more nurse practitioners in primary care." Smiles faded, faces froze and the room fell silent. An outraged doctor, the color in his face rising, stood to bellow at his impertinent colleague.