AbstractModern anaesthesia requires an appreciation of the potential to reduce perioperative complications through improved pre-assessment, risk stratification, individualised anaesthetic techniques and appropriate interpretation and response to intraoperative clinical signs and advanced monitoring. This chapter contains detailed discussion of cases relating to cardiopulmonary exercise testing (CPET) (case 2.3), intraoperative fluid management (case 2.1) and the prevention of accidental awareness under general anaesthesia (AAGA) (case 2.2). CPET allows objective testing of cardiopulmonary reserve prior to the stress of major surgery; the data produced enables patients and anaesthetists to make informed choices about perioperative management. This case describes the physiological principles and growing evidence base supporting its use. Intraoperative fluid management, and advanced monitors to direct it are the subject of increasing focus in modern anaesthesia. This case highlights the importance of understanding the strengths and limitations of the technology now available. AAGA (accidental awareness during general anaesthesia) is a highly feared complication of anaesthesia, both by patients and anaesthetists. This case discusses identifying those at risk, techniques to prevent AAGA and principles of managing cases when they arise.