Our characterization of how humans extract and process information depends on how we measure it, and the resulting quantification ultimately determines the applicability of this science in the design of systems to optimize and enhance human performance. Toward this end, the Potomac Institute’s new volume, Quantifying Human Information Processing, makes a significant and timely contribution. More than a collection of analytical literature reviews written by experts in their respective fields, each chapter explores its subject matter for heuristics and synthesis. This book should prove valuable to both research psychologists and human-system designers.