Armitage-Smith arrived at Birkbeck in 1896, and over the course of the next 22 years, transformed the Birkbeck Literary and Scientific Institution into Birkbeck College, University of London.

Armitage-Smith initiated a massive programme of restructuring, spurred on by a new generation of students and staff who were clamouring for reform. Armitage-Smith was the first Principal to be paid as a full-time Head of the college and he reciprocated by introducing a system of salaries for lecturers, when previously they had received directly the fees students paid for attending their classes.

Armitage-Smith also grouped the dozens of individual classes for the first time into some semblance of the faculty system we recognise today. He argued for Birkbeck’s joining the University of London to educate the ordinary citizens of London, as in contrast to Oxbridge, it should be a “people’s university.”