In this article, David Powlison examines developments in modern integration: the attempt to combine psychology with Christian faith. Powlison tracks three “phases” of the movement over time: the preliminary phase, the professionalization phase and the popularization phase. He looks at modern integrationists through three types: “The Flea Market” (chaotic integrationism), “The Big Umbrella” (sophisticated integrationism) and “Good Intentions Notwithstanding” (covert integrationism). Powlison gives examples of integrationists in each category and examines their views of anthropology and epistemology. He closes with an analysis of how biblical Christians should view and use psychology.