[2][3] It consisted of the Wellcome Library and an Academic Unit.
The former was and is a world-class library collection owned and managed by the Wellcome Trust and staffed by librarians including academic librarians who held honorary lectureships at University College London.
The Academic Unit was a group of university staff appointed at University College London that conducted a programme of university teaching, thesis supervision, seminars, conferences and publications.
In 1999 the Wellcome Institute for the History of Medicine was terminated, and in its place two new organisations were created: The Wellcome Library and the Wellcome Trust Centre for the History of Medicine at UCL.
Prof. Harold Cook was appointed Director of the Wellcome Centre at UCL from 2000 to 2009, while the following persons succeeded David Pearson as Librarians of the Wellcome Library.