Over the past decade, we have seen a rapid development of materials with controlled properties for a wide range of applications from large-scale construction to nanoelectronics. This would not have been possible without a strong contribution from materials science based on experimental studies. The methods and techniques available today allow us to reconstruct the real operation and use of materials with controlled properties and characterize them in real time.  In this talk, we will present the applicability and enormous potential of scanning X-ray nanodiffraction for in situ and in-operando studies. The Nanofocus Endstation of the P03 beamline at PETRA III (DESY, Hamburg), operated by Helmholtz-Zentrum Hereon, offers unique conditions for in-situ and in-operando experiments in combination with X-ray nanodiffraction. The highly versatile experimental setup is designed for structural analyses with submicrometer precision and allows non-destructive access to the interior and properties. The contribution of the P03 Nanofocus Endstation to materials science is demonstrated by the wide range of in-situ experiments already performed at the station, such as mechanical, thermal or electrical tests with organic and non-organic materials. Detailed technical specifications of the beamline and in-situ facilities will be presented as well as the results of the experiments.