Jack Wennberg has battled uncertainty in medicine-and foes of his findings-for 35 years. His weapons have been intellectual bravery and a dogged sense of doing the right thing. Now hailed nationwide for his iconoclastic ideas, he has just stepped down from leading the troops that he assembled at Dartmouth.

Thanks to an unusually collaborative, cross-disciplinary research culture, Dartmouth boasts the most comprehensive and advanced effort anywhere to develop effective alternatives to mammography.

One of the giants of 20th-century medicine-neurosurgeon Harvey Cushing-was bound and determined to pay homage to a seminal American physician who lived a century before him-Dartmouth Medical School founder Nathan Smith. It's a saga filled with historical coincidence.