The culmination of a pure research project in undergraduate mechanical engineering is presented. wherein the reader is invited to follow the student's investigation of hydrogen as an automotive fuel. Hydrogen cannot be considered as an internal combustion fuel without some evaluation of the general aspects of hydrogen energy. Fossil fuels are limited in supply, and an alternative energy source must be developed. The attraction of hydrogen is its minimal environmental impact, so the research is conducted from that perspective. Since the primary use of fossil fuels is as gasoline, the concentration is on hydrogen as an automotive fuel. The research includes history, current developments, benefits, limitations, cost, safety, implementation and possible competitors of hydrogen fuel. The most promising application is a compression-ignition engine designed specifically for hydrogen, with the onboard fuel stored as a cryogenic liquid.