Recognizing the educational potential of HistoryWorld, the Wellcome Trust (the world's largest medical research charity) commissioned Dr Carole Reeves to write for us an online history of medicine. Dr Reeves has done so in a fascinating and original way, by following seven important themes from the earliest times to the present. And she has accompanied each theme with a related timeline. We are extremely grateful to the Wellcome Trust and to Dr. Reeves for this valuable addition to our site.