The focus of the environmental policy-making has shifted noticeably during the last decade. From having played a fairly insignificant role in the 1980s and earlier, product-related environmental problems have attracted an ever-increasing interest from policy-makers, especially in industrialised countries in North-Western Europe. Considerable attention has been devoted to the concept of extended producer responsibility (EPR) and today this concept is spread to most OECD countries and also outside this group of countries. This dissertation shows how the concept was developed, presents a model for various types of responsibilities and defines the EPR concept as a policy principle for environmental improvements of products and product systems. Experiences from existing EPR systems are studied and complemented with an analysis of proposed system implementations. The results are combined with a model for how an EPR system can be developed in order to give the incentives for change to the relevant actors. Conclusions concerning how the details of EPR systems should be organised are presented, as well as a discussion about the advantages and disadvantages with involving various actors in the policy development process and the role of these actors in the implementation of the system.