Efficient portfolio diversification and successful active management can depend critically on how managers slice the investment universe. Authors Peter J.B. Hopkins and C. Hayes Miller provide a comprehensive exploration of stratification, considering countries, sectors, industries, and companies in their analysis. Readers will garner two primary insights from this Research Foundation monograph. First, a recent rise has occurred in the importance of industry sectors in global investing. Second, globally, stock selection may not be an inherently more profitable area of focus for money managers than country or sector allocation.