The Grenoble High Magnetic Field Laboratory (GHMFL) was built to meet the requirements of scientists for experiments implying the use of high magnetic fields. It is established in Grenoble, France. It is a French-German laboratory, jointly operated by the Max Planck Institut Air Festkorperforschung, in Stuttgart (MPI-FKF) and the Centre National de la Recherche Scientifique (CNRS). Scientists have access to the magnetic field facility provided they have written a proposal for experiments in high magnetic fields and have obtained the approval of the Program Committee to carry out their research. Since the foundation of the laboratory, the research effort has been mainly devoted to solid state physics (i.e. research on metals, superconductors, semiconductors, magnetism, etc.) which can be performed in a volume as small as a few cml. Five years ago the laboratory has undertaken the development of 20 MW magnets. Two of them are now in operation and deliver fields up to 30 T in a 50 mm room temperature bore. A 20 MW magnet is composed of two concentric 10 MW magnets. The outer 10 MW part alone achieves a field up to 10 T in a 376 min diameter bore. It is obvious that this large diameter is convenient for MHD flow studies under high magnetic fields.