The Middlesex Hospital in central London came to the attention of millions around the world when Princess Diana visited it in 1987.
It was the first hospital in the UK to have a dedicated ward for patients with HIV and Aids.
Thirty years ago photographer Gideon Mendel was given special access to the hospital to capture the work and lives of the people there, such as patient Stephen Feeney.
His photos, many of which have never been put on display before, form part of a new exhibition at the Fitzrovia Chapel.
