Contents: Introduction, Christopher Bajada and Friedrich Schneider. Taxpayer Behaviour and Motivations: Illegal, immoral, fattening or what?: how deterrence and responsive regulation shape tax moral, Lars P. Feld and Bruno S. Frey; Explaining taxpayer non-compliance through reference to taxpayer identities: a social identity perspective, Natalie Taylor; Getting on or getting by? Australians in the cash economy, Valerie Braithwaite, Monika Reinhart and Jenny Job. Measuring the Underground Economy - International Evidence: An international comparison of underground economic activity, Friedrich Schneider and Christopher Bajada; On the estimation and updating of the hidden economy estimates: the UK experience, Dilip Bhattacharyya; The shadow economy in OECD and EU accession countries - empirical evidence for the influence of institutions, liberalization, taxation and regulation, Domink H. Enste; The shadow economy in Norway 1980-2003: Some empirical evidences from voluntary sample surveys, Kari Due Andresen, Tone Ognedal and Steinar Strom; The underground economy in Canada, Lindsay M. Tedds. Detection, Prevention and Progress: Tax policy and the underground economy, Peter S. Spiro; Tax noncompliance in the United States: measurement and recent enforcement initiatives, Kim M. Bloomquist, Alan H. Plumley and Eric J. Toder; Tackling the underground economy in the UK: a government's response, Christopher Bajada; Recent government initiatives in tackling the underground economy in Australia, Christopher Bajada; Tax compliance strategies to tackle the underground economy, Simon James.