We propose a new investment strategy employing “factor funds” to systematically enhance the mean-variance efficiency of international diversification. Our approach is motivated by the increasing evidence that size (SMB), book-to-market (HML), and momentum (MOM) factors, along with the market...

Utilizing approximately 51,000 sample firms from developed markets over 1995-2014, we document a stark heterogeneity in global integration at the firm-level and study its implications for diversification. Specifically, the adjusted R-square, our integration measure, is widely distributed across...