In order to assist public procurement in facing up to environmental considerations, criteria have been developed in the Nordic countries over the last 15 years for a number of product groups both under national auspices and under the auspices of the Nordic environmental labelling scheme. All the countries involved have experienced that this task requires considerable resources. Within the project "Common Nordic Procurement Criteria? - a pilot study" an analysis was made of four different sets of criteria common to three of the countries. The pilot study concluded that there is an existing potential for establishing common procurement criteria, as well as opportunities for achieving them. The goal of the second project, "Proposal for a common Nordic format for environmental criteria for public procurement - a pilot project" was to identify a common Nordic format for environmental criteria as well as evaluating opportunities for future collaboration. The work on a common format has embraced many aspects concerning criteria and criteria development. Every attempt has been made to come up with practical solutions to cover all these aspects. The result of this work is a proposal for a common Nordic criteria format. The format is illustrated by five different product groups. This report also provides recommendations on how the Nordic countries should continue their cooperation in this field by establishing a Nordic criteria database on the Internet. This report is also available in Norwegian (Tema Nord 2006:598 Miljø og offentlige innkjøp – Felles nordiske innkjøpskriterier?)