Public procurement – the government's activity of purchasing the goods and services it needs to carry out its functions – is a subject of growing interest to academics and in the last two decades has emerged as a distinct area for legal study. Whilst, given the recent nature of this development, many aspects of public procurement law and policy remain unexplored by scholars, the use of procurement as a tool to promote social and environmental objectives – what we call ‘horizontal’ procurement policy – is one aspect that has always attracted interest. In part, this is because of its intersection with other policy areas such as labour relations, gender equality and environmental and energy policy. In most jurisdictions interest in the use of procurement as a policy tool has been increasing, not least because of its potential role in addressing the pressing issues of climate change and energy security and because increased outsourcing to developing countries has led to a resurgence of interest in the issues of fair working conditions and ‘fair trade’ in public contracts.

This subject has interested the co-editors of this book for many years. Sue Arrowsmith's interest has arisen from her broader interest in public procurement regulation. She first examined the use and regulation of procurement as a policy tool in the context of the Canadian system in Government Procurement and Judicial Review back in 1989 and she has since explored differing national approaches (for example, in the United Kingdom, South Africa and the United States) in research for, amongst others, the UK Office of Government Commerce and the UN, and in the book Regulating Public Procurement: National and International Perspectives (2000, with John Linarelli and Don wallace).