Recently, strikes of so called unions concerning occupational groups have attracted attention. It has often been demanded to contain such activities. In this regard a law concerning tariff uniformity in case of coexistance of different collective agreements has often been recognised as being a proper solution. The thesis examines whether a law concerning tariff uniformity in case of coexistence of different collective agreements would comply with Art. 9 III German Constitution. In this respect, the thesis presents the relevant constitutional structures and especially deals with the important consitutional question under which requirements statutory law could be identified as interference in Art. 9 III German Constitution. Based on the relevant structures, the thesis demonstrates that a law concerning a tariff uniformity has to be recognised as interference in Art. 9 III German Constitution. Such an interference would not be consistent with Art. 9 III German Constitution.