This book examines the scope of urban planning in Mexico through case studies of four municipalities - Campeche, Hermosillo, Leon and Morelia - that have recently updated their plans using new federal guidelines. We seek to advance a research agenda on the impacts of planning and its effectiveness by proposing some foundations for how to assess planning processes, as well as to provide guidance for the federal government of Mexico in its oversight of municipal planning practice and recommendations for the four cities we study. We begin with the concern that the debate over whether urban planning in Mexico “works” suffers from a lack of shared definitions about what is and is not within the scope of urban planning, and a shared conceptual framework for assessing the planning process. The case studies were conducted as part of a graduate studio in the Department of Urban Planning at UCLA. They rely on multiple interviews with planners and professionals in each city as well as documentary and data analysis, and literature reviews. We use a framework of five processes: creating a plan, implementing the plan, raising revenue to fund urban infrastructure, upgrading existing neighborhoods to ensure equal access across neighborhoods, and investing in new infrastructure to support growth. Each case presents a brief urban history and contextual data; a description of local government planning activities, the current plan, the city’s political history, and transparency in local planning; an assessment of planning processes, the mechanisms for changing land uses, and examples one infrastructure project and enforcement of land use rules; and an evaluation of the plan itself, including some GIS analysis local zoning and federal policy. The book’s recommendations fall into three areas: making plans into part of an ongoing and iterative process, increasing coordination between municipal budgeting and planning, and creating transparency and public input to the planning process. More specifically, we find that new plans often ignore successes and failures of prior plans, they do not periodically assess indicators to gauge impact, and discretionary changes in between plan updates diminishes the importance of the plan itself. In the second area, we argue that the scope of planning must be expanded. The plan should be integrated with the municipal budgeting process and municipalities in Mexico should work to generate more local revenues to adequately fund plans. Finally, in the third area, we recommend making planning documents, zoning maps, and basic data on urban conditions accessible to the public. A lack of transparency and the often opaque decision making processes harm the legitimacy of governance. We also outline how the federal government can play a role in advancing these recommendations for local planning processes.