Adequate fluid therapy is essential in the treatment of patients undergoingmajor elective surgery. Both fluid overload and hypovolemia are harmful during the perioperative phase, with an impact on mortality and morbidity. Objectives: To describe the physiological and clinical principles of volume therapy in the perioperative period, with a focus on dynamic assessment of volume response. Literature review based on PubMed using the terms fluid, high risk surgery, hypovolemia. Zero balance fluid therapy should be target-ed. In high-risk patients, hemodynamic management should be individualized and titrated through the use of therapy aimed at volume targets. Volume management and fluid overload can have a detrimental effect on postoperative results. Therefore, strategies to avoid fluid overload and to help assess the individual need for volume during and after surgery should be implemented to increase patient safety.