Over the last decade or so, the debate on the planning and development of the Paris (Île-de-France) region has revolved around two little words: “Grand Paris” (Greater Paris). Despite political and scientific controversies surrounding the future of the capital region, three major issues, different but interdependent in nature, have emerged: the economic development of Paris and its place on the world stage; socio-spatial justice and quality of life in the region (Section 3); and governance (Section 4). These three issues are key to understanding the processes under way in the Paris region in connection with the concept of a Greater Paris. The aim of this introduction to this special “Grand Paris” issue is to stimulate scientific discussion by exploring these issues on the basis of key stylized facts and the rationales of the various stakeholders, and by underlining the original contributions made by the different articles of this issue.