Abstract
Fish make up the bulk of the world’s fishing catch, and thus significantly contribute to food security objectives, particularly in developing countries. At the same time, however, fishing affects natural fish populations and is considered the primary driver of marine biodiversity decline. Exploitation directly affects the demography, and therefore the abundance of exploited stocks, but also their genetic diversity. More indirectly, fishing modifies habitats and species assemblages, and ultimately the structure and functioning of marine ecosystems, as well as the place occupied by fish. These various impacts of fishing are presented in this chapter, along with the main implications for the definition of sustainable fisheries management.