Every generation of scholars is faced with the task of reassuring itself of the foundations of its own discipline. In this sense, Die Grundlagen des Verfassungsrechts sees itself as a work on constitutional law and constitutional law scholarship - including, but not limited to, the Basic Law. The three-volume handbook ties in with the self-reflection processes of the science of public law and also sees itself as a safeguard of its results. Volume 1 presents various theoretical and methodological "approaches" to constitutional law and constitutional thinking and examines the contexts and conditions of validity and effectiveness of constitutional law. At the same time, the volume forms a reflective framework for the other volumes of the handbook: Volume 2 will analyze the central "categories" of constitutional law and constitutional thought, Volume 3 will be devoted to the various dimensions of the "order of rule" as an essential constitutional function.