The last four years in the financial markets have seen immense volatility, patchy liquidity, and fundamental shifts towards a new macro regime. However, that is not all, as behavioral, technological, and regulatory changes have caused market structural shifts in the trading environment. Execution management systems (EMS) have been at the forefront of these changes so have had to keep up. In this report, Celent examines the macro and micro trends in buy side EMS development to determine the factors that underlie the purchasing decisions of institutional investors and the areas in which vendors should be looking for differentiation.