ABSTRACT
Alien species are significant component of global change, and their occurrence is often associated with a negative perception of the impact on humans and biodiversity. Even though the numbers of introduced species across all taxonomic groups are high, counts of invasive species, those that are spreading and have impact, are much lower. Since the 1980s, invasions by exotic species have been considered across different groups of policymakers, researchers, and stakeholders as a significant problem for nature and economy. There is progress in understanding the basic questions of invasion ecology, management, and prevention issues. Unfortunately, they are rarely transformed into functional policy measures. In this entry, we review the current state-of-the-art understanding of biological invasions, impact assessment, and management of exotic species.
