A method for detecting a leak in a line system having a distribution line where the first end can be closed by a first valve and at the second end of which at least one consumer is arranged, a pressure sensor by means of which the pressure in the distribution line can be ascertained, and at least one second valve wherein at least one second valve is arranged between the pressure sensor and at least one of the consumers is disclosed. The method contains the steps of a) closing the first valve, b) ascertaining a first pressure reduction rate (PR1); c) closing the at least one second valve; d) ascertaining a second pressure reduction rate (PR2); and e) determining the region of the leak on the basis of the ascertained pressure reduction rates (PR1, PR2).