Luminosity upgrade of HERA

After six years of operation the electron proton collider HERA had reached a luminosity of 1.4·10³¹ cm^-2 s^-1 very close to the design value. We present an overview on the HERA upgrade project that pursues the goal to further increase the luminosity three-fold by the year 2000. The increase is achieved by reducing the beam cross sections at the IP to 120×30 cm² (RMS values). If furthermore design currents can be reached in both machines the improvement factor is up to 5. The upgrade involves a complete rebuild of the interaction regions as well as lattice modifications in the electron ring. Major issues of the project are superconducting magnets that will be installed inside the colliding beam detectors, unconventional normal conducting magnets, the handling of synchrotron radiation in the IR, and electron beam dynamics