At the end of World War II, Williams entered graduate school at the University of Kansas, where he worked under Dr. Byron Leonard. Leonard was interested in crayfish, the lobsterlike freshwater decapod crustaceans that are popular diet items in some areas, but surprising discoveries to pokers-about in Appalachian streams here on the East Coast. Leonard, who was struggling with an old, incomplete and poorly conserved collection at Kansas, suggested that a good master's thesis for Williams would be to work up the taxonomy of these imperfectly known Ozark Mountains crustaceans. Williams and Leonard became field partners in what was to develop into a five-year project. Although one can work from published literature, to do the best taxonomy, it is necessary to have access to the original monographs, collections and type specimens.
Type specimens are the original, preserved animals collected decades, or even centuries, earlier.
At that time, the best specimens were available at Harvard University or the National Museum of Natural History in Washington, D.C., which is part of the Smithsonian Institution. This latter contact was to enrich Williams during his entire professional life. The Ph.D. program at the University of Kansas required that one spend the summer at a marine station. This loss left a hole in his life that inspired him to help young biologists with their careers. When Williams completed his Ph.D. in 1951, there were no jobs for Ph.D crustacean researchers.