The GARTEUR Group of Responsables for Structures and Materials identified the need for an evaluation of fatigue crack propagation models. This resulted in a collaborative GARTEUR activity in which 13 variations of the F-27 transport spectrum were evaluated by 7 institutes and companies using in total 13 crack propagation prediction methods and models. It is shown that the predictions range from very conservative through accurate to unconservative. Follow-on work within the framework of GARTEUR is indicated.