The claim that high levels of engagement can enhance organizational performance and individual well-being has not previously been tested through a systematic review of the evidence. To bring coherence to the diffuse body of literature on engagement, the authors conducted a systematic synthesis of narrative evidence involving 214 studies focused on the meaning, antecedents and outcomes of engagement. The authors identified six distinct conceptualizations of engagement, with the field dominated by the Utrecht Group's 'work engagement' construct and measure, and by the theorization of engagement within the 'job demandstextendashresources' framework. Five groups of factors served as antecedents to engagement: psychological states; job design; leadership; organizational and team factors; and organizational interventions. Engagement was found to be positively associated with individual morale, task performance, extra-role performance and organizational performance, and the evidence was most robust in relation to task performance. However, there was an over-reliance on quantitative, cross-sectional and self-report studies within the field, which limited claims of causality. To address controversies over the commonly used measures and concepts in the field and gaps in the evidence-base, the authors set out an agenda for future research that integrates emerging critical sociological perspectives on engagement with the psychological perspectives that currently dominate the field.