Precaution intuitively and routinely informs decisions, yet proves both contentious and elusive when formally invoked in environmental regulation. Enshrined in the 1992 Rio Declaration on Environment and Development, the precautionary principle supports cost-effective action in situations where there are threats of serious or irreversible damage to the environment, despite the lack of scientific certainty. Whereas it now permeates environmental law within the European Union, it is frequently approached with scepticism in the USA.

In this concise, comprehensive and captivating book, Kerry Whiteside explores the meanings, utility and current interpretations of the precautionary principle. The author enriches his discussion with conceptualizations of precaution from the old and new worlds, providing an insightful and well-researched resource accessible to educated readers, both academic and practitioners. Although the author indicates that the ideas addressed in the book are targeted in the first instance to readers in the USA, where the principle ‘is not widely appreciated’ (p. ix), in my view this book would be equally appealing to Europeans and other cultures interested in understanding the philosophical underpinnings of the concepts surrounding the precautionary principle debate, whilst exploring the more profound and complex politics of its applicability within deliberative frameworks in modern societies.

The author is to be applauded for successfully guiding the reader through the origins of the principle, making it come alive initially with reference to the heated transatlantic dispute on genetically-modified (GM) organisms. The book subsequently discusses clearly and succinctly the arguments advanced in support for and against the application of the precautionary principle in decision-making, referring to the characteristics of ‘new’ risks and the appropriateness of tools available for their assessment and management. In one of the most historically interesting sections of the book, the third chapter highlights the strong roots of precaution in the USA, which permeate environmental and health regulation although the principle in itself has no official status within federal law. This chapter traces the evolution of the principle's acceptability and applicability across both sides of the Atlantic, relating these in part to ideological incongruity with liberal environmentalism, thus seeking to clarify the perceptual and positional distinctions between the USA and Europe. I almost expected some reference here to the three strands of the UK government review of GM initiated in 2002, comprising examinations of the science, of the costs and benefits of growing GM crops and the national public debate.

The prose develops to skilfully discuss issues key to the management of environmental risks, sometimes only implicitly acknowledged in relation to the precautionary principle, including: conceptualizations of nature; the capabilities of science; the limitations of risk-assessment methods in the face of serious, global and uncertain risks; the role of science and value-judgements in decision-making; individual and social responsibilities (and duties); and the wider implications of incorporating precaution in the governance of environmental issues (as prominently indicated within the book's title). The author weaves a logical and sophisticated argument drawing upon Cass Sustein's and Hans Jonas's reflections, amongst others, towards interpreting the precautionary principle and arguing a case in its support.

In the final chapter and concluding section, the author explores the contribution of deliberative methods such as consensus conferences to the interpretation of precaution, within the tendency to democratize decision-making processes, in the face of uncertainty and limitations of cost-benefit risk assessments. I was pleased to see that the author's critical reading of these methods warned against considering them a panacea, thus reflecting other cautious evaluations by prominent social science researchers. My interest was refreshed by the author's proposals for a precautionary approach to be more widely conceptualized to openly acknowledge and encompass the positive contribution of politics, understood as the engagement of communities in learning and arbitrating environmental change of which they are part, taking responsibility for actions invariably affecting the interconnected systems that sustain life on this planet.

This book provides a well researched, argued and informed discussion of perspectives on the precautionary principle from both sides of the Atlantic. The author builds upon these as contributions towards a more attentive, rich and interconnected approach to precaution. This work dutifully cites the relevant peer-reviewed literature, supported by chapter endnotes and a comprehensive index.