Since the publication of previous reports on how undeclared work is being tackled in the 27 Member States of the European Union (EU27) and Norway (Eurofound, 2008, 2009), the ongoing recession took hold. The aim of this report is to provide an updated overview of the policy approaches and measures that have been implemented to tackle undeclared work since the beginning of the recession in 2008. The first important finding of this synthesis report is that many new policy measures are being pursued in Member States of the EU27 and Norway that are transferable to other sectors and countries. If the accompanying knowledge bank is used by Member States to identify new possibilities for policy initiatives, so as to expand their existing repertoire, an important objective will be achieved. This report provides pointers of potentially good practice policy measures that Member States might wish to further consider. An executive summary is also available - see Related content.