The father of instrumental microanalysis, Raymond Castaing, died on April 10, 1998. With him, we lost one of the outstanding figures in modern materials characterization. He was creative and innovative in physical research, in invention of instruments, in teaching, and in science management. At a time when science tends toward an inexorable division into smaller and more specialized provinces, an investigator of truly wide-ranging interests and capabilities, in the best traditions of renaissance curiosity, has left us.