Oxygenation and ventilation are two distinctively different process, although they are interrelated. Ventilation involves the physiology of moving air in and out of the lungs, generally delivering oxygen to alveolar spaces and removing carbon dioxide. Oxygenation, which generally requires adequate ventilation, involves the physiology of delivering oxygen to alveolar spaces, transferring it across the alveolar-capillary membrane, and delivering it to the body's organs. In addition to findings evident on physical examination, such as vital signs and skin color, pulse oximetry and capnography are useful tools to evaluate and monitor oxygenation and ventilation, respectively. Emergency medical services clinicians should administer supplemental oxygen judiciously. Noninvasive positive-pressure ventilation can improve respiratory distress by facilitating ventilation and augmenting oxygen delivery to alveolar spaces. Mechanical ventilation represents maximum support. Important aspects of ventilator management include understanding associated physiological changes, knowledge of ventilator parameters, and complications to watch for.