This article discusses incoherence between tax and development policies, a relatively new area in the debate on policy coherence for development, using a case study of the Netherlands. Dutch business entities play a key role in tax avoidance structures of multinational corporations. We argue that the Dutch tax regime facilitates the avoidance of substantial amounts of tax revenues in developing countries when compared to the Dutch aid budget. As domestic tax revenues are an important source of financing for development, this suggests that the Dutch tax policy is incompatible with the Dutch policy on development co-operation. The lack of policy coherence is largely unintended but it has structural and political causes.