Researchers and decision-makers increasingly favor the adaptation strategy of managed retreat to address urban floods exacerbated by climate impacts. But as opposed to contexts in the Global North, national governments, development banks, and other knowledge brokers in the Global South employ retreat-related activities to disproportionately relocate informal settlers – who lack legal land tenure – to ostensibly lower-risk areas. Many of these relocation programs target risk-prone settlements with feasibility profiles similar to those that the U.N. and other global bodies instead recommend upgrading in-situ with climate-sensitive modifications. This dissertation examines two questions: (1) why do governments engaging in retreat policy in informal settlements tend to favor relocation rather than in-situ approaches, and (2) under what conditions would these governments be open to employ in-situ adaptation approaches more often? As an exemplar, this study evaluates retreat-related policies in Manila, Philippines because of the city’s high exposure to urban flooding, large number of informal settlers, and extensive application of both relocation and upgrading programs. It uses text and map analysis, participant observations, and 20 virtual interviews with public, private, and nongovernmental representatives to investigate activities of three national retreat-related programs between 2010 and 2016 at five project sites selected as case studies. Evidence suggests that state-led relocation patterns in the Philippines more often align with economically-driven land use changes than disaster-driven or planned modes of retreat. Government logics justified both in-city relocations using short-term time horizons and onsite upgrades without mitigation measures for future climate impacts on a project-by-project basis. By beginning to detail key place-based factors, logics, and practices driving government-led retreat in the name of urban flood prevention, this study opens up a menu of adaptation pathways and strategies tailored to different contexts and forms of decision-making. Planning scholars and practitioners can use these results to identify and facilitate more diverse, locally appropriate forms of adaptation in the Global South. Rather than approaching retreat as an exercise for relocating people, stakeholders throughout the Global South can integrate land use and livelihood considerations – when feasible – to ensure that residents can safely stay-in-place as long as possible while they plan future movements.