This book introduces Computational Fluid Dynamics (CFD) as a vital design tool for architects, urban designers, and planners. In a time defined by climate pressures and urban density, understanding airflow, heat, and pollution is essential for creating liveable, resilient environments. Moving beyond its engineering roots, CFD becomes here a creative, generative instrument?helping designers visualize how air moves through courtyards and city canyons. The book bridges simulation science with design practice, offering clear explanations of turbulence modelling, mesh generation, and boundary conditions, supported by examples using ANSYS Fluent and ENVI-met tools. Emphasizing accessibility over complexity, it transforms CFD from a technical afterthought into a method for innovation. Through case studies and environmental applications, readers learn to integrate simulation into design thinking?testing ideas, improving performance, and climate-responsive spaces for a sustainable urban future.