Oliver was a researcher at the Oxford Institute for Sustainable Development (Department of Architecture, Oxford Brookes University), and from 1978-88 was Associate Head of the School of Architecture. He is an Honorary Fellow of the Royal Institute of British Architects (1999) and was awarded an Honorary Doctorate by the University of Gloucestershire (2007). He has argued that vernacular architecture will be necessary in the future to "ensure sustainability in both cultural and economic terms beyond the short term." He is well known for his 1997 work Encyclopedia of Vernacular Architecture of the World. Spanning 3 volumes and 2500 pages, it includes contributions from researchers from 80 countries. , he was at work on a book to be called the World Atlas of Vernacular Architecture.

He is also a leading authority on the blues. His studies of American traditional music did much to spread interest in the blues and included early research into the influence of Islamic music from North Africa on its origins. His work, which began in the 1950s, includes interviews, field work and research in recording and printed sources tracing the origin and development of African American music and culture from the time of slavery and before.

Oliver's Collection of African American Music and Related Traditions was established in 2007 with the support of the European Blues Association at the University of Gloucestershire.

Some of his architectural writings:

Blues books: