Invaded is a story about pollution...but not the more commonly reported oil spills, litter or filthy smoke-stacks. ""Invaded"" is about biological pollution - the plants and animals that have spread around the globe on the back of human movement, those that have traversed the boundaries of natural habitats and have begun to erode their new adopted environment. In telling the story of biological pollution, Leonie Joubert documents the grave consequences of humankind's intended and unintended introduction of alien species into South Africa. While some rivers have lost their natural fish populations, the west coast is choked over with mussels from a far-off country; the Cape Floral Kingdom's rare plants have come under increasing threat; sensitive renosterveld has been reduced to a few isolated islands of resistance; dams and lakes have been taken over by an umbrella of aquatic plants; and water is being consumed voraciously by thirsty alien trees. Working in close collaboration with the Centre for Invasion Biology at Stellenbosch University, Leonie Joubert brings the general reader a scientifically sound yet accessible and important book. ""Invaded"" is, however, not a story of despair. Instead, it encourages scientists, citizens and policy-makers to continue with their efforts to contain and eradicate invasive alien species. It is a book for the guardians of the South African environment.