"New" approaches to governance have attracted significant scholarly attention in recent years. Commentators on both sides of the Atlantic have identified, charted and evaluated the rise and spread of forms of governance, forms which seem to differ from previous regulatory and legal paradigms. In Europe, the emergence of the Open Method of Coordination has provided a focal point for new governance studies. In the US, scholarship on issues such as collaborative problem-solving, democratic experimentalism, and problem-solving courts exemplify the interest in similar developments. Hitherto there has been little reflection on the legal and constitutional dimension of the modes and forms of governance being appraised. This book, presenting the results of an international research project, demonstrates considerable diversity in terms of the policy sectors and subject areas under examination, ranging across a wide range of policy areas, including the environment, education, anti-discrimination, food safety and many others. While some chapters concentrate on the operation of new governance mechanisms in a federal and multilevel context and others look at the relationship between public and private mechanisms and settings, what all the contributors share in common is the pursuit of effective mechanisms for addressing complex social problems, and the challenges they raise for our understanding of law and constitutionalism, and of legal and constitutional values.