The High Performance Light Water Reactor (HPLWR) is a Light Water Reactor (LWR) operating at supercritical pressure (25MPa). It belongs to the six reactors currently being investigated under the framework of the Generation IV International Forum. In Europe, investigations on the HPLWR have been integrated into a joint research project, called High Performance Light Water Reactor Phase 2 (HPLWR Phase 2), which is co-funded by the European Commission. Within 42 months, ten partners from eight European countries working on critical scientific issues shall show the feasibility of the HPLWR concept. The final goal is to assess the future potential of this reactor in the electricity market. Within the first year of the project, mainly design tasks of the reactor core, the pressure vessel and its internals have been carried out and codes were adapted for supercritical fluid. Material oxidation experiments were performed and heat transfer was investigated numerically.