Prevention is the most cost-efficient and effective method against invasive alien species. Halting the establishment of potentially invasive species in the first place is the first line of defense. Governments conduct customs checks, inspect shipments, conduct risk assessments and set quarantine regulations to try to limit the entry of invasive species. However, global inspection and risk analysis capacity is usually not sufficient.

It is also important to develop economic tools and incentives for the prevention of introductions, and to educate the general public and raise awareness so that informed decisions can be made about how to limit introductions and their spread. Invasive alien species are a global issue that requires collaboration among governments, economic sectors and non-governmental and international organizations. Individuals also have a large part to play, including policymakers, consumers, horticulturalists, landowners, educators, youth and recreationists.