ConclusionThis paper is an essay to investigate the effect of managerialoptimism and some other CEOs personal characteristics on ori-enting firm’s investment policy. Departing from a sample of 475large manufacturers American firms traded at the NYSE stock mar-ket and using an adjusted Q-investment model, we empiricallydemonstrate that the managerial optimism has a great impact onexplaining why a firm may run investment cash flow sensitivity andthen make its investment policy depending to its financing strategy.Our results also conclude that some other CEOs personal character-istics’ such as financial education and their ownership participationin their own firms can explain distortions in corporate investmentdecisions since they reduce investment cash flow sensitivity.