The Molecular Haematology and Cancer Biology (MHCB) Unit at the Institute of Child Health and Great Ormond Street Hospital is responsible for both basic and clinical cancer research within the joint institution. In the most recent national assessment of research in higher education (December 2001), the MHCB Unit received a 5*A rating, as did the entire Institute of Child Health. This is the best possible rating and signifies that it is a Unit of outstanding excellence, with both staff and research output on a par with the very highest level of international science.