Joined the University of Sheffield in 1991 as a lecturer in dermatology whilst continuing as a practising dermatologist for the NHS in Sheffield. Previously, a Registrar in Dermatology at the Royal Hallamshire Hospital, Sheffield, and a Registrar in Respiratory General Medicine at Leeds General Infirmary.

Professor Cork has been closely involved with research in many areas of dermatology; including Atopic Eczema(dermatitis), Psoriasis, Vitiligo and the Genetics of Skin Disease. Major current research work is aimed at identifying gene–environment interactions in the development of atopic dermatitis leading to skin barrier breakdown and the understanding of how topical agents interact with the skin barrier; using this information to enhance the treatment of atopic dermatitis.

Currently the Head of Sheffield Dermatology Research in the Department of Infection, Immunity & Cardiovascular Disease at the University of Sheffield Medical School and Honorary Consultant Dermatologist to both Sheffield Children´s Hospital NHS Foundation Trust and to Sheffield Teaching Hospitals NHS Foundation Trust.