Professor South was one of the first criminologists to highlight the consequences of the privatisation of policing and criminal justice in the UK. In the early 1980s, he worked with MPs and pressure groups to campaign for regulation of private security companies, door security, and private investigators.

He has held teaching and research posts in London and New York, and is an Adjunct Professor in the School of Justice at Queensland University of Technology, Brisbane, an Honorary Visiting Professor in the School of Law and Social Sciences, University of Suffolk, and a Research Associate, Centre for Rural Criminology, University of New England, Armidale, New South Wales.

In 2013 he received a Lifetime Achievement Award from the American Society of Criminology, Division on Critical Criminology and Social Justice, and in 2022 received the Outstanding Achievement Award from the British Society of Criminology. He was elected a Fellow of the Academy of Social Sciences in 2014. From January 2015 to August 2021 he was Director of the Centre for Criminology. He is a member of the Board of Trustees of Open Road, the drug and alcohol services charity.

At the University of Essex, between 2005 and 2013, he served as Pro-Vice Chancellor for the Faculty of Law and Management, and for Academic Partnerships, and prior to this served as Director of the Health and Social Services Institute, Head of the Department of Health and Human Sciences, and Director of Health Partnerships.

He is European Editor of Critical Criminology and an Associate Editor of Deviant Behavior. He has previously served on the editorial boards of Sociology, the International Journal of Drug Policy, the Howard Journal of Criminal Justice, and the International Journal for Crime, Justice and Social Democracy.

In 2022-23 he is serving on the award committee for the American Society of Criminology, Division of International Criminology, Freda Adler Outstanding Scholar award, and Is a member of the Technical Working Group on Global Analysis on Crimes that Affect the Environment, Research and Trend Analysis Branch, UNODC.

Professor South has published more than 30 books and journal special issues as author, co-author, editor or co-editor, and over 200 articles and book chapters.