John's research interests focus on spatial planning and urban regeneration, including international comparative approaches. He has worked on a range of projects including the following: tax-based policy mechanisms for urban regeneration (ESRC, involving Universities of Dundee and Ulster); the use of arts and culture as a means of achieving sustainable regeneration (Carnegie Trust for the Universities of Scotland); and the effects of cruise passenger terminal developments in historic port cities (Carnegie Trust for the Universities of Scotland).

John has worked as a practitioner in spatial planning in London and elsewhere and has worked in academia since 1992. He is an active member of the Royal Town Planning Institute and currenly chairs the Partnership Boards of London South Bank University and Hong Kong University. He also represents UK planning schools on the RTPI's Membership Assessment Advisory Group, and he represented non-Russell Group Universities on the RTPIs' 2017 Education Policy Review Group. He was a member of the Scottish Government's 2017 Planning Review Working Group which advised on the 2017 Scottish Planning Bill.