Modern ventilators employed in intensive care units (ICUs) display in real time and breath by breath flow (V̇), volume (V), and pressure (Paw) curves, both as a function of time and as a loop. Data obtained from curve analysis can help the physician to understand the interactions between the patient and the ventilator. The right interpretation of information provided from modern ventilators allows real time monitoring of the actual needs of the patient, ensuring a custom ventilatory support and reducing the risk of complications that can increase the mortality and prolong the ICU length of stay. In patients undergoing mechanical ventilation, measurements of respiratory mechanics can be performed at the bedside in dynamic (no flow interruption) or static (occlusion techniques) conditions. From these, it’s also possible to derive the values of pulmonary compliance and airway resistance.