In this short contribution, the question as to whether the exhaustion of local remedies rule in the context of diplomatic protection pertains to the admissibility of the claim or the substance of the wrongful act. In the first case the exhaustion goes to the requirements of claims and litigation; in the second case, it goes to the existence of the substantive legal position. The various arguments made in legal writings are discussed and practice as far as is available is examined. The position taken by this author is that overall the admissibility explanation better fits the configuration of the law of international responsibility in this subject matter, but that also both explanations are legally possible and have arguments to their advantage.