After various positions in the United Kingdom, Dalgleish joined the
Royal Flying Doctor Service in
Mount Isa,
Queensland, then progressed through positions at various hospitals in
Brisbane, Australia, before moving to the
Ludwig Institute for Cancer Research in Sydney. In 1986, he was appointed to a consulting position at
Northwick Park Hospital, in 1991 he was made Foundation Professor of Oncology at
St George's, University of London, In 1997, he founded Onyvax Ltd., a privately funded
biotechnology company developing cancer vaccines, where he held the position as Research Director; it was dissolved in 2013. Dalgleish is a member of the medical board in
Bionor Pharma. Dalgleish is on the scientific advisory board of
Immodulon, and has stock options in
Immunor AS, a disclosure he made in order to have his research work published. During the COVID-19 pandemic, Dalgleish was a proponent of the
lab leak theory. While still not generally accepted, this remains a live debate, and it has been claimed that the support of
Jay Bhattacharya and
John Ratcliffe for the lab leak theory will bring "explosive documents" to light in 2025. ==2015 candidacy for Parliament==