https://doi.org/10.1177/0091829618774332 Missiology: An International Review 1–14 © The Author(s) 2018 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0091829618774332 journals.sagepub.com/home/mis Beyond people group thinking: A critical reevaluation of unreached people groups Peter T. Lee Trinity Evangelical Divinity School, USA James Sung-Hwan Park Trinity Evangelical Divinity School, USA Abstract Since its inception at the 1974 Lausanne Congress, the concept of “unreached people groups” (UPG) has revolutionized global mission. Today, “people group thinking” represents perhaps the predominant paradigm in global mission. Yet for all its influence, few have carefully examined UPG’s questionable underlying assumptions. This article critically reevaluates two central tenets of UPG. First, using biblical and sociocultural analysis, we assess the conceptual foundation of UPG—the idea of the people group. Second, we engage theologically with mission strategies that arise from UPG. We conclude that UPG relies upon flawed biblical, theological, and sociocultural assumptions, and propose that missiology move beyond UPG in theory and practice. Keywords unreached people groups, homogenous unit principle, unity in diversity, evangelical mission Corresponding author: James Sung-Hwan Park, Trinity Evangelical Divinity School, 858 Ridge Rd, Highland Park, IL 60035, USA. Email: hkamugae@gmail.com 774332MIS 0 0 10.1177/0091829618774332Missiology: An International ReviewLee and Park research-article 2018 Article