Time-resolved experiments in powder diffraction are limited by the long time required to record spectra with current detectors. A major improvement can be made by using a massively parallel X-ray detection system together with a fast read out. The Mythen detector (Microstrip system for time-resolved experiments) has been built for the Powder Diffraction Station of the Material Science beamline at the Swiss Light Source to meet these requirements. The specifically developed read out chip (Mythen chip), the detector system and first measurements are shown.