Advanced design methods contribute to the effective long term operation of high temperature components and guarantee low technical risk and high economical advantages. Along with the generation of advanced creep data, modelling and scatterband analyses are necessary to generate design curves and lower bound properties inclusive. Besides, in order to develop life prediction methods variable creep experiments lead to properties for single-stage and multi-stage loading. Further, the knowledge of multiaxial creep behaviour is of high future interest. The development of methods to transfer uniaxial material properties to multi-axial loading situations is a current challange. Different methods are established in order to describe creep crack initiation as well as crack propagation. A knowledge of the influence of creep processes on tolerance to pre-existing defects promotes the long term usability of components.