This thesis develops design-led flood adaptation strategies for the city of Manila. With much ground already covered on cross-disciplinary approaches in flood risk management, this thesis considers the discussion of flood adaptation through the lens of ecological urbanism and architectural design. The issue is the fluid edge between city and water and is captured in the term ‘floodscape’, to give definition to a cityscape affected by fluctuating water levels. The thesis argues for the importance of urban design as the key driver to integrate the environmental and social concerns of the city in a holistic and critical way. Floodscape Urbanism therefore can be understood as a potential bridge between urbanism and hydrological cycles, with design providing a crucial framework within which to think about and act on environmental, technical, economic and socio-cultural challenges. Manila, as an extreme case of a flood-prone city, presents the challenge of having to balance vital flood management with creating places suitable for urban life that many cities in the global south are facing or will face. The focus of the design research is the exploration of how holistic flood adaptation approaches can be applied and translated to the particular context of Manila, both as a strategic design process on a master plan level and as architectural design propositions at a neighbourhood scale. The written thesis establishes the theoretical framework for design-led flood adaptation and in the main chapters reflects on design from the scale of the city to the neighbourhood, and on the possibilities and limitations of architectural intervention. If architecture is to engage with the dilemma of cities at flood risk, the starting point is for architects to view flood adaptation not as a solution, but as an essential restructuring of assumptions in the way we live in flood zones, and the conditions that are necessary to support that life.