Since its founding in 1847, the AMA has been the physician’s powerful ally in patient care and an unrivaled force that promotes the art and science of medicine and the betterment of public health.

From its pioneering work to protect the public from potentially dangerous treatments, to championing the safety and efficacy of vaccines, to advocating for seat belts to be standard in all American automobiles, the AMA has often been at the forefront of sweeping movements to improve the health of our nation.

To comprehensively detail the AMA’s impact is far beyond the scope of this article, but a selective approach can be revelatory as the organization celebrates its 175th anniversary on May 7. A timeline of key dates in AMA history is one place to start, and you can learn more below about seven other critical junctures—one for roughly every 25 years in the organization’s history—when the AMA rose to meet the moment in medicine.

My latest for the AMA. The whole shebang.