After a BSc in microbiology from the University of Strathclyde and a PhD in bacterial genetics at Warwick University, George did postdoctoral work on the genetics of E. coli cell division (Edinburgh University) before a lectureship at the University of Kent. He then moved to Warwick University, where he became Professor of Microbiology (1993) before coming to Cambridge in 1996. He also did research work at the CNRS, Marseille, France (Senior Ciba-Geigy Fellow) and Celgene Corporation, New Jersey, USA (Celgene Sabbatical Fellow).
Some of his professional activities in recent years include: Council of the Microbiology Society; Convenor, Cell and Molecular Biology Sectional Committee, Royal Society of Edinburgh; Scottish Science Advisory Council; Board of Directors and Advisory Committee on Science, James Hutton Institute; President, British Society for Plant Pathology; Governing Council, John Innes Centre and the Scottish Crop Research Institute; Council of the Federation of European Microbiological Societies; International Secretary and Council of the Society for General Microbiology; Science Unions Committee, Royal Society, and Pathogen Sequencing Advisory Group, Wellcome Trust Sanger Institute. He has served on many research funding, advisory and science quality review committees in the UK and Europe, and on the Scientific Advisory Board, NSC Technologies (Illinois, USA) and various Editorial Boards of microbiological journals.