János Szentágothai was an eminent, creative and renowned neuroscientist, who made pioneering and seminal discoveries contributing to our current understanding of brain functions. His vision of the brain as a network of specific populations of nerve cells, each engaging in selective operations and self-organizing into modules, has provided the framework and stimulus for generations of neuroscientists. His irrepressible curiosity and enthusiasm for the beauty in the organization of the brain never faded. He had a towering intellect and was a great humanist. Szentágothai was born in Budapest, Hungary, in 1912 and died in his native city in 1994. He was educated and worked in Hungary. During the six decades of his scientific activity, he made remarkably original and lasting contributions to the neurosciences, including the exploration of basic architectural features of many brain areas, the functional-anatomical bases of elementary brain operations such as reflex arcs, the vestibulo-ocular system, the brain control of hormonal regulation, general organizational principles of the neuraxis, the organization of the cerebellum and the modular organization of the neocortex. He left for posterity not only his discoveries, which have stood the test of time, but also a vigorous school of pupils as well as a large number of friends and admirers. Thanks to him neuroscience is one of the strongest scientific fields in Hungary today.