This thesis investigates the dynamic behaviour of a rotating shaft containing a transverse crack through a finite element formulation. The rotor is modelled as a shaft–disk–bearing system with four lateral degrees of freedom at each node. Both Euler–Bernoulli and Timoshenko beam formulations are considered in order to evaluate the influence of shear deformation and rotary inertia on the predicted dynamic response. The local flexibility introduced by the transverse crack is obtained from fracture-mechanics-based compliance relations. The crack-induced bending compliances are converted into equivalent directional reductions of the second moment of area for the shaft element containing the crack. This procedure produces an anisotropic stiffness reduction associated with the fully open crack condition.