Since 1975, Jack has been positioning ROI as a critical measure of value for non-capital investments. His work (along with mine, since 1997) has touched professionals well beyond the boundaries of learning and development to include human resources, meetings and events, marketing, and even humanitarian efforts. And with about 110 books authored, co-authored, or edited to our names, he and I have had the opportunity to share our work in measurement and evaluation, specifically the ROI Methodology