This thesis explores possible transformations of peri-urban areas in the Jing-Jin-Ji megaregion (China) in order to improve the region’s performance in terms of environmental and social sustainability. Peri-urbanity in East-Asia - or Desakota, a term coined by Terry McGee in the 1990s - can be conceptualized as a combination of easing urban agglomerations and different forms of rural transformation. Being bypassed by economic metropolitan structures, it forms a diffuse mix of agricultural, industrial, and residential patches. Dramatic levels of air pollution and the loss of agricultural land threaten environmental and social structures. What was once called the hinterland has lost its original function. The shortcomings of spatial planning practices and regional governance should be counteracted by readjusted principles of urbanism. It is hypothesized that integration and compactness can be suitable tools to contribute to the sustainable development of megaregions, if they adapt to the complexities and scales posed by mega-regionalization. This hypothesis is explored through in-depth analyses on multiple scales and their translation into (design) strategies. European case studies help to make transitions between well-known icons of regional planning and design, and the unknowns of the Chinese megaregion. The methodology lays out an agenda that leads to three concrete outcomes. Firstly, the “Desakota Dilemmas” clarify the difficulties of balancing environmental and social concerns. Secondly, the “Desakota Strategies” present proposals for alternative forms of peri-urbanization that are based on the diversity of village communities and the detailed analysis of spatial pre-conditions. Thirdly, the “Jing-Jin-Ji Planning Framework” synthesizes the outcomes of analysis and design, and presents recommendations that advocate for a type of regional planning that is based on collective action, multi-scalar cooperation, and the recognition of uncertainty.