Illicit financial flows (IFFs) associated with commodity trade erode the tax base of resource-rich developing countries. Efforts to curb IFFs and reform taxation stumble over enhanced North–South tensions but remain crucial to helping poorer countries mobilise domestic resources for development. The 17th volume of International Development Policy examines this key part of the wider agenda to restore trust in the multilateral system, calling for a more transparent, effective and equitable trade and tax framework. Based on a six-year multidisciplinary research project encompassing academic institutions in commodity exporting and trading countries, its 24 authors offer a mix of theoretical and empirical contributions and discuss findings of macro- and micro-level studies. The book sheds new light on issues such as addressing push and pull factors through domestic and international policy measures, the preferences of key stakeholders for short-term fixes versus long-term policy reforms, and prescriptive approaches and other options to address tax base erosion in resource-rich developing countries.