My Thesis deals with the income tax treatment of dividends, interest and royalties, which are produced by a person or, a joint-stock company, liable to pay Austrian tax. As a result of cross-border transactions, the claim to taxation between states frequently enters into competition, because the country in which the activity or transactions occurs is also entitled to exercise its taxing jurisdiction. The methods for avoiding double taxation in such situations are represented by the Thesis, however, not the situation of affiliated companies. My methodology is to, first, demonstrate the national tax regulations for each of the three different income components. Next, I explain the tax regulations of the OECD Model Tax Convention on Income and on Capital, and finally the tax regulation of the European Union. Bilateral tax treaties that differ from the OECD Model Tax Convention are mentioned as needed. The income resulting from direct investments and from a capital investments funds, as well as real estate investment trust are explained. In the course of writing this Thesis, a new law, the Budgetbegleitgesetz 2011, was promulgated. Because of its new systematology, which affects the essential norms of my subject, the relevant regulations were incorporated. In addition the European Court of Justice has rendered a judgment of fundamental significance in the case Haribo and Salinen AG. Owing to its particular importance for serious issues relevant to the subject, the Thesis refers also to the decision of the Court and its consequences. There is, in addition, an attempt to give an overview of the differing views on tax relief in the residence state of the taxable subject in accordance with the bilateral tax treaties. Finally are mentioned tax havens and the means to obtain tax advantages or reduce the tax charges.