The selected papers in this volume are arranged in chapters, each with an introductory essay. The purpose of the arrangement is to illustrate the process of scientific discovery at work. Neil Bartlett's field is that of powerful oxidizers. The early chapters tell the story of the oxidation of the oxygen molecule and the discovery of xenon chemistry. His work in noble-gas chemistry is summarized. Succeeding chapters show how metastable fluorides such as AgF3 and NiF4 came to be prepared at ordinary temperatures and pressures, and how they have provided the most potent oxidizers and fluorinators ever prepared.