The MRC-Wellcome Trust Human Developmental Biology Resource (HDBR) is organised from two sites: the Institute of Genetic Medicine, Newcastle, and the Institute of Child Health, London. The HDBR is an ongoing collection of human embryonic and fetal material ranging from 3 to 20 weeks of development. Tissue, slides, RNA/DNA and tissue arrays are available to the international scientific community. Material can either be sent to registered users or our In House Gene Expression Service (IHGES) can carry out projects on user’s behalf, providing high quality images and interpretation of gene expression patterns. Gene expression data emerging from HDBR material is added to our gene expression database which is accessible via our HUDSEN (Human Developmental Studies Network) website.