Patient selection for left ventricular assist device (LVAD) therapy is the most important process in obtaining a successful outcome. Evaluation requires assessing the appropriateness for device implantation based on need and risk of LVAD implant to the patient. Appropriate patients can be selected without the need for invasive hemodynamic measurements and selection can be based on symptoms, appropriateness of medical therapy, and on the need for inotropic therapy. Assessing the risk of LVAD therapy to the patient requires evaluating the degree of organ dysfunction and technical factors. Patients should be offered the option of LVAD therapy if they meet criteria for need, possess the potential for organ recovery, and have appropriate operative risk. (C) 2003 by The Society of Thoracic Surgeons.