The character of different surge cycles is described, and the corresponding influence on the dynamic loading of the blades of axial flow compressors is discussed. It is shown that essentially fatigue is governed by the rapidity of loading or unloading of the blading. Test results from an experimental 4-stage axial flow compressor showed that the induced dynamic stresses in the blades, which reach about three times the steady gas bending stresses, can lead to fatigue failure. Reference is also made to previous surge tests carried out on a gas turbine installation, which indicate that a good correlation can be expected between the calculated and the measured pressure distribution. Mention is made of the fatigue failure of the rotor blades of an industrial compressor submitted to a long period of intense surging.