Peter F. Stanbury, MSc, DIC, Visiting Lecturer at University of HertfordshirePeter's career as Principal Lecturer at the University of Hertfordshire encompassed teaching and research in microbial physiology and fermentation technology. He spent sabbatical periods at ICI Fermentation Products, the Warren Spring Laboratory and in the laboratory of Professor Ayaaki Ishizaki, Kyushu University, Japan. He also held managerial responsibilities as Head of Biochemistry and Microbiology, and as Associate Head of the School of Life Sciences. Peter is now retired but returns as a Visiting Lecturer in the field. He is a member of the Microbiology Society and was previously Treasurer of the Society and Convener of the Fermentation Group. Prior to joining the University of Hertfordshire, Allan was a research scientist with ICI working on aspects of fungal physiology and plant tissue culture. His career as Senior Lecturer at the University of Hertfordshire encompassed teaching in microbiology and research in microbial physiology and fermentation technology. Allan retired from the University and continued as a Visiting Lecturer but also combined his interest in local history and microbiology in his research on the history of the brewing industry in Hertfordshire. Allan has taken an advisory role in the development of this edition but the influence he had on the previous two editions very much remains. He is a member of the Microbiology Society and was previously convener of its Teaching Group. Stephen J. Hall, MSc, PhD, Senior Lecturer at University of HertfordshireStephen's career as Senior Lecturer at the University of Hertfordshire has encompassed teaching in numerous fields across the Chemical, Biological and Environmental Sciences together with research in effluent treatment, microbial physiology and fermentation technology. He is a member of the Society of Chemistry and Industry, and a Fellow of the Higher Education Academy.