Zvi Griliches, a world-renowned pioneer in the field of productivity growth, has compiled in a single volume his pathbreaking research on R&D and productivity. Griliches addresses the relationship between research and development (R&D) and productivity, one of the most complex yet vital issues in today's business world. Using econometric techniques, he establishes this connection and measures its magnitude for firm-, industry-, and economy-level data. Griliches began his studies of productivity growth during the 1950s, adding a variable of knowledge stock to traditional production function models, and his work has served as the point of departure for much of the research into R&D and productivity. This collection of essays documents both Griliches's distinguished career as well as the history of this line of thought. As inputs into production increasingly taking the form of intellectual capital and new technologies that are not as easily measured as traditional labor and capital, the methods Griliches has refined and applied to R&D become crucial to understanding today's economy.