X-ray Nanodiffraction is exceptionally well suited to investigate microstructurized materials. This non-destructive technique can be used to obtain microstructural information such as residual stress, structural homgeneity, grain maps or texture with sub-µm spatial resolution. Data can be collected from a variety of different crystalline and semi-crystalline materials (metals, biomaterials, compounds, even glasses) and thanks to using long focal distance X-ray nanofocusing with a wide X-ray energy range, experiments can even be performed under the demanding conditions of an "in situ" experiment, i.e. while external parameters are being modified. Hydrostatic pressure, nanoindentation force, tensile stress, fluid shear, electric and magnetic fields - all of these parameters have already been successfully combined with nanodiffraction experiments at the Nanofocus Endstation of beamline P03 (PETRA III, Hamburg). This instrument was built by the University of Kiel and is now part of the German Engineering Materials Science Center (GEMS) i.e. it is operated by Helmholtz-Zentrum Geesthacht. It is one of only few places in the world where the experimental conditions for X-ray nanodiffraction are provided and it offers a hard X-ray beam with a size of only 250 x 350 nm².