To present a set of conclusions based on what has been analysed and discussed throughout this book, we begin by taking stock of the most important ideas that emerge from each of its seven chapters, and then refer to the elements constituting the most significant contributions to the position, definition and understanding of one of the largest urban agglomerations in the world. Set in the Latin American context, the Mexico City Metropolitan Area (ZMCM) shares certain features with the great metropolises of the world and the region, while other features are different. Their evolution and problems highlight the enormous challenges it faces.

The ZMCM is an extensive urban area encompassing land from 76 small political-administrative units, belonging to three major political-administrative bodies, called states or federative entities. One of these federal entities is Mexico City, divided into 16 smaller administrative units (alcaldías). Some parts of this book refer to Mexico City, while other chapters and sections analyse issues on a broader geographic scale, such as the ZMCM.

The first chapter studies the structure, dynamics and territorial distribution of the population in the ZMCM, in addition to reviewing the main guidelines of the population policy. The differential growth of the population over large areas of the ZMCM can be explained by the dissimilar behaviours of fertility, mortality, migration and intra-metropolitan residential mobility. The highest population growth occurred in municipalities on the inner periphery, while the central city saw a repopulation.

The total fertility rate in the ZMCM is one of the lowest nationwide. In 2002, it reached the generational replacement rate, 2.1 live-born children per woman, continuing to decrease to values of 1.7 live-born children per woman in 2020. For its part, the crude mortality rate in the ZMCM was lower than in the national context in 1980, with 5.7 deaths per 1,000 inhabitants per year. This indicator reached a tipping point in 2000, and thereafter began to increase, surpassing the country in 2004 and reaching a rate of 6.4 deaths per 1,000 inhabitants per year in 2020. The performance of fertility and mortality in the ZMCM has resulted in natural growth below that of the country.