For the rest of the war he worked at Boots in Nottingham on the manufacture of pharmaceuticals, and was awarded a BSc in Chemistry by the University of London.

In 1945, he was appointed assistant professor at University College, where he was awarded a PhD in biochemistry for the successful conclusion of a research project.

In 1979 he was elected a Fellow of the Royal Society and in 1991 delivered the Leeuwenhoek Lecture on the subject of the influence of the host on microbes that cause disease.

[6] In the 1993 Queen's Birthday Honours Smith was appointed a Commander of The Most Excellent Order of the British Empire (CBE) for services to the Ministry of Defence.

Previous Harry Smith Memorial Lecturers include Dame Sally Davies,[8] Professor David Holden, Professor Pascale Cossart, Arturo Casadevall, Liz Sockett, Mihai Netea, Bonnie Bassler, and Gordon Dougan.