The main objectives of this Doctoral Thesis are the development and implementation of a fatigue crack growth (FCG) test methodology for elastomers, and the determination of the influence of various test parameters and of the material structure on the FCG behavior. To overcome difficulties in FCG testing with non-planar crack growth, a pure shear specimen modified with a faint waist was used in all crack growth experiments. In terms of the general FCG concept applied, two different characterization approaches have been analyzed in detail, the Tearing Energy and the J-Integral method. Whereas the Tearing Energy method is a straightforward method based on global force-displacement measurements, which delivers FCG data in a comparatively short time, the J-Integral method is a more complex method in terms of measurement technique and data analysis, since it operates on various two-dimensional data fields. For typical testing parameters the Tearing Energy was compared to the corresponding J values, which showed a good correlation. With the measurements using the Tearing Energy the influence of parameters like test frequency and crack tip radius have been analyzed and the difference in FCG behaviour for typical material grades has been investigated. The measurements on materials, where the structure was changed by modification of the carbon black content, showed the dependence of the FCG behaviour on such material properties and the difference between two rubber types.