The adult respiratory distress syndrome (ARDS) represents a common denominator of acute lung injury leading to alveolar flooding, decreased lung compliance, and altered gas transport. In the absence of specific etiology and therapy, the management of ARDS remains largely supportive. Ubiquitous use of intermittent positive-pressure ventilation with positive end-expiratory pressure (PEEP) improves arterial oxygenation but with some risk of pulmonary barotrauma and decreased cardiac output. The recent understanding of lung inflation as a modulator of right heart afterload and the effect of the right ventricle on global cardiac performance continues to redefine optimal patterns of ventilatory and hemodynamic intervention in ARDS.