Switzerland and Austria signed the MLI at the first opportunity on June 7th, 2017. Because of constitutional concerns Switzerland, however, does not accept an alongside application of the MLI and its tax treaties, but insists on a mutual agreement stipulating the modifications of a tax treaty. Austria accepted this approach making the tax treaty with Switzerland a covered treaty. Madeleine Simonek aims to provide an overview of the reservations and options of Switzerland to the MLI and how the tax treaty between Austria and Switzerland will (or will not) change based on the MLI or the conclusion of the mutual agreement respectively.