There is an interdiction of interest in the Islamic religion. This work illustrates the prohibition of interest (ribâ) according to the Sharia and the Koran. It also presents alternative non-interest earning financing models. A short introduction gives not only an overview of Islamic banking, but also its compatibility with the Sharia and its control over prohibitions in general. Thereafter, a presentation on the interdiction of interest in the Islamic religion follows. In this connection, the legal basis, the different goods of ribâ including the forms of the interdiction of interest and the difference of opinion between the schools of law will be dealt with, as there are different financial models according to the Sharia with regard to the undertaking of banking transactions. Therefore three different systems are chosen to illustrate this. Whilst one model, the so called musharaka, is based on equity capital, the others, murabaha and tawarruq, are based on debt capital. There are also legal aspects concerning compatibility with the Sharia and the national law. This problem will be showed by an explanation of the English court practice, an illustration of which, for example, is the judgement of the Londons Court of Appeal in the case of the Shamil Bank of Bahrain vs. Beximco.The ON-rule 142001-1 is the link to Austria which serves as an orientation for bank and credit institutions to reconcile sharia-compliant financial products with the Austrian legal system. In this, the interdiction of interest from the viewpoint of the Austrian legislation will be outlined and demonstrated. Following this, the work once more addresses the previously described financial models and examines them from the perspective of the ON-Rule.