Based on the case law of the European Court of Human Rights (ECtHR), the following contribution analyses the significance of national legal bases in relation to the restriction and assurance of convention-guarantees. The ECtHR, through a variety of its judgments, has dealt extensively with the requirements of legal bases; the recent decision in Vukota-Boji? v Switzerland, for instance, perceptively demonstrated the court’s ostensible criteria. Legal traditions, and the requirements of legal delegations, differ between contracting States; in some countries, for example, case law is of great importance. The ECtHR, therefore, does not apply formal legal criteria, but measures normative foundations on a material scale.