Consumer engagement is increasingly emphasized in healthcare initiatives and has been a priority in healthcare reforms. Consumer engagement takes multiple forms, including increased involvement of consumers in their own care, in organizational design, and in broader policy decision-making processes. Determining the effectiveness of such involvement requires both effective measurement and empirical study, both of which have yet to be standardized or fully explored. In this review, we examine both existing measurement tools for consumer engagement and current empirical knowledge regarding the outcomes associated with each of three levels of consumer engagement. Although measurement and results at the level of direct care are more established, measurement of consumer engagement, let alone its effects at the organizational design or policy level, is less well developed. Building on our review, we make suggestions for how to fill the current gaps in understanding the measurement and outcomes of consumer engagement.