For outcomes research, what are the implications of seeing the patient as a decision maker? In the current medical environment, greater emphasis is placed on the role played by the patient in clinical decision making. In the past 2 decades, considerable work has been done to identify and measure decision-related outcomes, including knowledge about the treatment options (risks and benefits), satisfaction, anxiety, decisional conflict, and involvement in the decision process. Attempts to improve these decision-related outcomes involve patient decision aids, which convey patient-specific information and sometimes help patients proceed through an explicit decision-making process. These interventions have produced positive results, especially with respect to improving patient knowledge. Future research is needed to understand which aspects of the interventions work and for what types of patients. Research is also needed to better understand the decision making process of patients who do not use decision aids.