Patients have the potential to play an important role in preventing medical errors. Yet little is known about how to effectively engage patients in this role as a "vigilant partner" in care. Respondents were asked to assess the perceived effectiveness of fourteen recommended actions for preventing medical errors. The findings indicate that most of the actions are viewed as effective. However, respondents also indicate that they are unlikely to engage in many of the recommended actions. Having a greater sense of self-efficacy in being able to prevent medical errors is significantly linked with a greater reported likelihood of engaging in preventive action.