Alistair Stephen was educated at South African College School (SACS) and at UCT, where he obtained the BSc (with distinctions in Chemistry and Physics), MSc and PhD. He then proceeded to Oxford University on a Rhodes Scholarship, duly completing the DPhil under supervision of the legendary Sir Robert Robinson, who during that period was awarded the 1947 Nobel Prize for Chemistry. On his return to South African in 1949 he worked first at the CSIR in Pretoria, before his appointment as a lecturer in Chemistry at UCT in 1951, and in 1962 as Mally Chair of Organic Chemistry, a position he occupied until his retirement in 1987. During this period he headed the Department of Organic Chemistry, which was part of the School of Chemistry at that time, and also established and directed the CSIR Carbohydrate Research Unit. The latter represented a consolidation of his seminal scientific contributions in the area of structural studies on polysaccharides and glycoconjugates of bacterial and plant origin. He produced upwards of 180 research publications, including research articles, reviews and book chapters. His scholarly life extended well beyond his retirement, and included compilation and publishing in 2005 of a booklet “The Department of Chemistry, University of Cape Town: A History”, representing his interest in and loyalty to his alma mater.