In my dissertation with the title European tax law aspects of cross-border pensions, a study based on Dutch tax laws and regulations regarding employees and pension providers, I investigate whether there are any unjustified obstacles with regard to cross-border pensions in Dutch tax laws and regulations regarding employees and pension providers. If there are any, I will present a solution to eliminate these obstacles. I will focus on the member states of the European Union (EU) and the countries that belong to the European Economic Area (EEA). The central question of my dissertation is the following: “Tax impediments can be a major obstacle to the internal market for occupational retirement provisions. Are there such obstacles in Dutch tax laws and regulations? If so, to what extent are they justified and proportional and what are possible solutions to eliminate the unjustified or disproportional impediments?” I will answer the questions arising from this problem for both the cross-border employee and the cross-border pension provider. The following European freedoms are relevant in answering the questions: the free movement of workers (Article 45 of the Treaty on the Functioning of the European Union (TFEU)), the freedom of establishment (Article 49 TFEU), the freedom to provide services (Article 56 TFEU) and the free movement of capital (Article 63 TFEU).