Implementation Shortfall at Wikipedia.)">Implementation Shortfall is the formal name for the slippage in investment return as an individual security is purchased or sold. This term represents the difference between the potential proceeds (changing a position by X amount of units at a Y certain decision price) and what is actually realized (after all transaction costs, including commissions, fees and taxes). Transaction Cost Analysis is formal method of evaluating how effective an asset manager minimizes Implementation Shortfall at Wikipedia.)">Implementation Shortfall. (More on Implementation Shortfall at Wikipedia.)