Being, at the same time, a crossroads, a settlement territory, production and transformation area, and a leisure place, the Mediterranean basin is threatened by intense anthropic pressure. For millenaries, human activities clearly impact all the compartments of the Mediterranean environment, from soils to fresh water, from sea to biosphere, or from the critical zone (The critical zone covers the thin outer layer of Earth’s surface, extending from the top of the vegetation canopy down to the groundwater, involving a mix of biological, physical, and chemical processes) to the atmosphere. In this overview chapter, as an introduction to more detailed and better-targeted chapters of this book, we consider the various human activities with a perspective on their effects on the atmospheric compartment, and so their impact on air quality and regional climate. In a bottom-up approach, we describe the extent of the urbanization processes, the industry and ship emissions to the atmosphere, and the dynamics of the primary extraction activities and tourism activities. In addition, we illustrate how much the increased occurrence of wildfires is linked to anthropogenic forcings and discuss the impact of wildfires on both air quality and climate. Finally, integrating this information, we show how the effects of this large-scale air pollution can be effectively detected and monitored from space.