Henry William "Bill" Wyld was Emeritus Professor of Physics at the University of Illinois at Urbana Champaign. Wyld was a theoretical elementary particle physicist, gifted with an understanding that was imaginative, profound, and clear. In his early career, Wyld worked in low- and high-energy physics on weak interactions and several problems related to K-meson proton scattering. Wyld is particularly noted for his significant theoretical contributions related to the effects of the breakdown of quantum mechanical symmetry properties, written shortly after the discovery of parity violation in 1957, that presented detailed calculations of a number of effects to be expected. This work enabled various experimental groups to correlate and evaluate their results. Wyld took advantage of supercomputing capabilities as these were being developed to run large-data simulations; he always pushed for more computing power to answer fundamental problems.