The purpose of this book is to examine the wider scientific and social contexts of modern plant breeding and agriculture. We will begin by examining the historical development of plant breeding over the past two centuries, before focusing on the dramatic changes of the last two decades. Perhaps the best-known recent development in plant breeding is the emergence of genetic engineering, with its attendant social and scientific controversies. But, as we shall see, GM crops and ‘agbiotech’ (agricultural biotechnology) are just one manifestation of a more extensive series of seismic changes that have profoundly altered the course of plant breeding since the 1980s. Today, in the middle of the first decade of the twenty-first century, plant breeding and crop improvement are at an historic crossroads. On one hand, are the tried and tested breeding methods that underpinned the Green Revolution and enabled us to feed the expanding world populations in the twentieth century. More recently, however, governments across the world have largely dismantled their applied research infrastructures and have greatly reduced the capacity for public-good applications of newly emerging breeding technologies, including transgenesis. Much of this institutional restructuring occurred as part of the ideologically driven privatisation of public assets in the 1980s and 1990s. The resulting depletion of public sector breeding has left a void that was filled by a few private sector companies who applied a new paradigm of crop improvement based on transgenesis – and from this, the agbiotech revolution was born.