This book introduces a groundbreaking approach to urban design, addressing site-specific challenges arising from the impacts of climate change. It provides an overview of the most relevant climate change impacts and related adaptation strategies, aligning with sustainable development goals. Nature-based solutions (NBS) are some of the most significant adaptation strategies, yet the book addresses the lack of quantitative approaches for their design. A design approach and related methodology that can be used by designers with different levels of complexity is presented, discussing its applicability and limitations according to selected key performance indicators and related thresholds. Such methodology and the related tools are applied to case studies with a focus on the performance of NBS in improving thermal comfort (microclimate regulation) and reducing flooding risks (stormwater retention). A final workflow for a coupled performance-driven design approach is presented for readers, offering a pathway to define design strategies based on site-specific key performance indicators. The target audience includes practitioners, urban designers and planners, researchers, and anyone interested in urban environment design, nature-based solutions, and computational approaches to sustainable design.