The goal of administering medical interventions is to help patients live longer or live better. In keeping with this goal, there has been increasing interest in taking the "voice" of the patient into account during the development process, specifically in the evaluation of treatment benefits of medical interventions, and use of patient-centered outcome data to justify reimbursement. Patient-reported outcomes (PROs) are outcome assessments (OAs) used to define endpoints that can provide direct evidence of treatment benefit on how patients feel or function. When PROs are appropriately developed, they can increase the efficiency and clinical relevance of clinical trials. Several PROs have been developed for OA in specific infectious diseases indications, and more are under development. PROs also hold promise for use in evaluating adherence, adverse effects, satisfaction with care, and routine clinical practice.