This book contends that environmentalism lacks a realistic view of social change and that an increased engagement with social theory is a key way forward to the goal of sustainability. Anthony Giddens is a social theorist of world renown but his work has not received a great deal of attention from within environmentalism. This book argues that Giddens' work is a rich vein for environmentalism as he provides a social theory - structuration theory - rich in concepts for understanding society, a valuable description of modernity in his later works and outlines policy ideas that are highly fruitful. This book reconstructs Giddens flawed understanding of nature as a "created environment" to theorize nature as existing in modernity. When the concept of contradiction from structuration theory is connected to Giddens' work on modernity with nature integrated, an understanding of modernity as composed of two dialectics - local-global and part of-apart from nature - is revealed. These dialectics are the sites at which the outline agenda for policy development must be aimed and this book will suggest such an agenda aimed at navigating these dialectics for social change towards sustainability.