Veteran environmental journalist Fred Pearce used to think of invasive species as evil interlopers spoiling pristine 'natural' ecosystems. Most conservationists would agree. But what if traditional ecology is wrong, and true environmentalists should be applauding the invaders? In The New Wild, Pearce goes on a journey to rediscover what conservation should really be about. He explores ecosystems from Pacific islands to the Australian outback to the Thames estuary, digs into the questionable costs of invader species, and reveals the outdated intellectual sources of our ideas about the balance of nature. Keeping out alien species looks increasingly flawed. The new ecologists looking afresh at how species interact in the wild believe we should celebrate the dynamism of alien species and the novel ecosystems they create. In an era of climate change and widespread ecological damage, we must find ways to help nature regenerate. Embracing the 'new wild' is our best chance.