The aim of this research is to simulate fatigue crack propagation in ductile materials subjected to proportional and non-proportional, cyclic loading conditions. For the materials under consideration, it is expected that non-proportional hardening has a major influence on the crack initiation and further evolution. The first part of the present work focuses on the modeling of the constitutive response for non-proportional cyclic loading conditions. The hardening mechanisms considered here are isotropic and kinematic hardening in conjunction with a deformation-induced, formative and a rotational change of the yield surface. The latter is captured by a fourth-order tensor which is introduced in the von Mises yield function. A first attempt to model such a material behavior was presented in Dafalias et al. [1]. The model is formulated thermodynamically consistent and corresponding material parameters are calibrated experimentally. In the second part of this work the constitutive equations are extended by a further internal variable, the phase field variable, to describe ductile crack growth. [1] Dafalias Y.F., Schick D., Tsakmakis Ch., A simple model for describing yield surface evolution during plastic flow. Deformation and Failure in Metallic Materials, 169-201, 2003.