Climate change has become one of the most important and challenging global policy fields. Attention has primarily focused on the successes and failures of states and intergovernmental organisations but many more actors are involved and contribute solutions. The contributions to this book assess the different potentials of existing schemes. They scrutinise how very different programs at national and international levels seek to marry complex public and private goals in and across industries addressing wide groups of firms. Lessons from these programs can help design and improve programs but they also show different types of pitfalls. Lessons learned are relevant not only for climate policy, but for the many other policy fields where private voluntary programs are active.