The invention of Markowitz (1952) mean-variance (MV) optimization altered the course of 20th century finance from security valuation to portfolio risk management.  The Markowitz frontier is a model of long-only institutional investment behavior representing a universal framework for asset management theory and practice.  The Capital Asset Pricing Model (CAPM) is MV preference theory based on Von Neumann and Morgenstern game theory rationality axioms.  CAPM theory was instrumental in the development of a 20th century multi-trillion dollar institutional quantitative asset management industry.