Tax capacity—the policy, institutional, and technical capabilities to collect tax revenue—is part of a deeper process of state building that is essential for achieving the sustainable development goals. This Staff Discussion Note shows that developing countries have made some progress in revenue mobilization during the past decades. However, much more is needed. We find that a staggering 9 percentage-point increase in the tax-to-GDP ratio is feasible through a combination of tax system reform and institutional capacity building. Achieving this calls for a holistic and institution-based approach that focuses on improving policy, administration and legal implementation of core taxes. The note offers practical lessons and guidance, based on IMF capacity building experience in this area.

This report responds to the February 2016 request from the G20 for the IMF, OECD, United Nations and World Bank Group to: “...recommend mechanisms to help ensure effective implementation of technical assistance programs, and recommend how countries can contribute funding for tax projects and direct technical assistance, and report back with recommendations at our July meeting.” The report has been prepared in the framework of the Platform for Collaboration on Tax (the “PCT”), under the responsibility of the Secretariats and Staff of the four mandated organizations. The report reflects a broad consensus among these staff, but should not be regarded as the officially endorsed views of those organizations or of their member countries.

There is a widespread concern that, in some parts of the world, governments are unable to exercise effective authority. When governments fail, more sinister forces thrive: warlords, arms smugglers, narcotics enterprises, kidnap gangs, terrorist networks, armed militias. Why do governments fail? This book explores an old idea that has returned to prominence: that authority, effectiveness, accountability and responsiveness is closely related to the ways in which governments are financed. It matters that governments tax their citizens rather than live from oil revenues and foreign aid, and it matters how they tax them. Taxation stimulates demands for representation, and an effective revenue authority is the central pillar of state capacity. Using case studies from Africa, Asia, Eastern Europe and Latin America, this book presents and evaluates these arguments, updates theories derived from European history in the light of conditions in contemporary poorer countries, and draws conclusions for policy-makers.

Would better state institutions increase tax collection, or would higher tax collection help improve state institutions? In the absence of conclusive guidance from theory, this paper searches for an empirical answer to this question, using a panel dataset covering 110 non-resource-rich countries from 1996 to 2017. Employing a panel vector error correction model, the paper finds that tax capacity and state institutions cause and reinforce each other for a wide range of country groups. The bi-directional causality results suggest that developing tax capacity and building state institutions need to go hand in hand for best results, particularly in developing countries. Based on the impulse response analyses, the paper also finds that the causal effects in advanced economies are generally low in both directions, while in developing countries, both tax capacity and institutions shocks have larger positive impacts on institutions and tax capacity, respectively.

Effective tax systems are a critical building block for increased domestic resources in developing countries, essential for sustainable development and for promoting self-reliance, good governance, growth and stability.

This report responds to the February 2016 request from the G20. The report has been prepared in the framework of the Platform for Collaboration on Tax (the "PCT"), under the responsibility of the Secretariats and Staff of the four mandated organizations. The report reflects a broad consensus among these staff, but should not be regarded as the officially endorsed views of those organizations or of their member countries. The request arises in the context of increased recognition of the centrality to development of strong tax systems and of the importance of external support in building them, and a correspondingly increased willingness of advanced economies to provide substantially greater financing and other support for this. In that context, the report uses the experiences of the international organizations to analyze how support for developing tax capacity can be improved.

An empirical finding by Gaspar, Jaramillo and Wingender (2016) shows that once countries cross a tax-to-GDP threshold of around 123⁄4 percent, real GDP per capita increases sharply and in a sustained manner over the following decade. In this paper, we attempt via four case studies—Spain, China, Colombia, and Nigeria—to illustrate that the improvements in tax capacity have been part of a deeper process of state capacity building. We discuss the political conditions that supported tax capacity building, highlighting three important political ingredients: constitutive institutions, inclusive politics and credible leadership.

Issues of taxation and development, which have long been a central concern of the IMF, have attracted wider and renewed interest in the last few years. This paper reflects on three broad lessons of experience: that developing countries differ vastly in tax matters, and in ways that are less than fully understood; that the history of ‘big ideas’ in guiding tax reform for developing countries is decidedly mixed; and that the value of the emphasis often placed in this context on ‘informality’ is decidedly limited. It also asks whether ideas of ‘state building’ emphasized in some of the recent literature are likely to lead to practical advice much different from that commonly offered now.

Abstract: An effective tax system is fundamental for successful country development. The first step to understand public revenue systems is to establish some commonly agreed performance measurements and benchmarks. This paper employs a cross-country study to estimate tax capacity from a sample of 104 countries during 1994-2003. The estimation results are then used as benchmarks to compare taxable capacity and tax effort in different countries. Taxable capacity refers to the predicted tax-gross domestic product ratio that can be estimated with the regression, taking into account a country's specific economic, demographic, and institutional features. Tax effort is defined as an index of the ratio between the share of the actual tax collection in gross domestic product and the predicted taxable capacity. The authors classify countries into four distinct groups by their level of actual tax collection and attained tax effort. This classification is based on the benchmark of the global average of tax collection and a tax effort index of 1 (when tax collection is exactly the same as the estimated taxable capacity). The analysis provides guidance for countries with various levels of tax collection and tax effort.

This report responds to the February 2016 request from the G20. The report has been prepared in the framework of the Platform for Collaboration on Tax (the “PCT”), under the responsibility of the Secretariats and Staff of the four mandated organizations. The report reflects a broad consensus among these staff, but should not be regarded as the officially endorsed views of those organizations or of their member countries. The request arises in the context of increased recognition of the centrality to development of strong tax systems and of the importance of external support in building them, and a correspondingly increased willingness of advanced economies to provide substantially greater financing and other support for this. In that context, the report uses the experiences of the international organizations to analyze how support for developing tax capacity can be improved.