Because of their inherent complexity, urban brownfield regeneration projects are long-term operations. The study of the evolution from urban brownfield site to a new—and ideally sustainable—neighbourhood through a regeneration process has led to the identification of five key steps: Backgrounds, Initiators, Guidelines, Legal Basis, and Realization. This chapter highlights the specific issues encountered during these different steps. Thus, our early reflections on the future of an urban brownfield at the regional and metropolitan levels concern the Background and Initiator steps. The formulation of a coherent project to overcome negative perception and foster a shared vision relates to the Guidelines steps. The transition from the urban to the architectural project is dealt with during the Legal Basis and Realization steps. Finally, issues concerning the multiple forms of participatory processes and the evaluation of sustainability objectives must be taken into consideration throughout the regeneration process. These reflections provide a foundation for developing a series of measures and more concrete lines of action.