Bachelor Thesis from the year 2022 in the subject Law - Tax / Fiscal Law, grade: 2,0, Rhine-Waal University of Applied Sciences, language: English, abstract: Tax planning is a practice used by many corporations in order to minimise their tax paid while being able to maximise their profits. One common way to undertake such conduct is by increasing the negative components of the tax base computation, for example, the interest expense deductibility. This practice is deemed harmful by many lawmakers, as it will imperil its tax legislation. Hence, to tackle this behaviour, the European Union has adopted an Anti-Tax Avoidance Directive in 2016, where the rules on interest expense as a tax planning tool are addressed in Article 4. The Directive is to be transposed into the Member States' tax laws. Nevertheless, there are some concerns on the comparability between the national rules implementing this Directive and the existing fundamental freedoms that are the cornerstone of the European Union. This thesis examines the possible infringements of the Directive's transposition to the fundamental freedoms enshrined in the Treaty of the Functioning of the European Union. Some recommendations with regard to ameliorating the identified incompatibilities are also given by using comparative legal research.