In the last five years, plasma source ion implantation (PSII) research at the University of Wisconsin-Madison, has encompassed work in the areas of plasma physics, diagnostics, ion-material interactions’ modeling, materials science issues, and a broad spectrum of industrial applications of PSII technology. The third generation PSII system is presently under construction. Three methods of plasma generation, namely, electron impact method, glow discharge, and radio frequency have been successfully employed. In the following article the highlights of the above facets of PSII research activities have been presented.