OECD has for many years collected information on, and analysed the environmental effectiveness and economic efficiency of, various instruments instruments used for environmental policy.

The analyses were brought together in An OECD Framework for Effective and Efficient Environmental Policies, prepared for a 2008 ministerial meeting. Much of the work has addressed economic policy instruments, such as environmentally related taxes and tradable permit systems.

These instruments can bring about a given environmental improvement at least cost to society as a whole and provide lasting incentives for the development of new technologies. Work has also been done on Greener Public Purchasing programmes and voluntary approaches for environmental policy.

Work has also been done to understand better how different environmental instruments interact when they are used in combination. In some situations, two or more instruments can underpin each other, like an energy tax and an energy efficiency labelling scheme.

In other situations, the existence of one instrument will largely render the application of another instrument redundant. Like any other policy, environmental policies should be carefully assessed both prior to their implementation and after they have been in place for some time, and OECD is doing much work to help in this regard. In particular, a meta-analysis of "values of statistical lives"  is being carried out - helping countries to assess the benefits of environmental policies that reduce mortality among affected populations.

A number of countries have in recent years extended producers' responsibilities  to include the post-consumer phase of a product. OECD has done work aiming to help governments to understand what is needed to establish cost-effective EPR programmes.

The environmental impacts of the instruments applied also depend crucially on the compliance ensurance system in place. A recent study examined a range of environmental compliance assurance systems in selected OECD member and non-member countries.