This article considers, from a German perspective, whether a taxpayer should be required to waive his domestic remedies before arbitration under a tax treaty. The article first examines the problem: the legal nature of the arbitration procedure, the situation under the mutual agreement procedure, the arbitration procedures, and the inconsistency of different requirements. The article then considers other questions: the scope of the waiver and the justification for requiring a waiver. The article concludes with possible solutions to the problem.