Returning military service members and veterans (MSMVs) experience a wide range of stress-related disorders in addition to social and occupational difficulties when reintegrating to the community. Facilitating reintegration of MSMVs following deployment is a societal priority. With an objective of identifying challenges and facilitators for reintegration of MSMVs of the current war era, we critically review and identify gaps in the literature. We searched 8 electronic databases and identified 1,764 articles. Screening of abstracts and full-text review based on our inclusion/exclusion criteria, yielded 186 articles for review. Two investigators evaluating relevant articles independently found a lack of clear definition or comprehensive theorizing about MSMV reintegration. To address these gaps, we linked the findings from the literature to provide a unified definition of reintegration and adapted the social ecological systems theory to guide research and practice aimed at MSMV reintegration. Furthermore, we identified individual, interpersonal, community, and societal challenges related to reintegration. The 186 studies published from 2001 (the start of the current war era) to 2015 included 6 experimental studies or clinical trials. Most studies do not adequately account for context or more than a narrow set of potential influences on MSMV reintegration. Little evidence was found that evaluated interventions for health conditions, rehabilitation, and employment, or effective models of integrated delivery systems. We recommend an ecological model of MSMV reintegration to advance research and practice processes and outcomes at 4 levels (individual, interpersonal, organizational, and societal). (PsycINFO Database Record