As a child my parents took me to the source of the River Danube, a mere trickle of water destined to become a mighty river flowing past Vienna and Budapest to the Black Sea. I have chosen two examples, the discovery of p53, a tumor suppressor, and the discovery of insulin to show how great discoveries, like rivers, are insignificant and vulnerable at the beginning, but develop into mighty streams of science and medicine. There is as yet no end to these rivers of discovery, and their impact will be felt for years to come...