In this study we analyse factors that predispose to risk and we value the importance of quality and reliability into operating theatre. Patient safety result from ability to plan and manage organizations able to reduce probability of mistakes (Prevention) and to recover and contain their consequences (Protection). The principal motives of mistakes are: - deficiency of sharing procedures between different professional figures for risk prevention; - deficiency of an effective integration between professional figures in operating theatre; - deficiency of charitable precise run to guarantee the continuity of interventions on patient. A risk management program have to take care on this sentinel events and to set up a survey-information system to characterize risks and correction strategies. To prevent patient change, wrong side identification, not working devices or deficiency of surgery materials, it would be useful for operating theatre figures and for anesthetists to work out all together a procedure for admission in operating theatre and a pre-operating check list. The best way to carry out a safety and quality attendance based on standardized procedures and protocols, is to set up risk management firm units. It is necessary to activate and to adjust survey system and effective management training.