Dr Brent Elliott is Historian at the RHS and has worked there for almost 40 years. He is the author of Victorian Gardens (1986), Treasures of the Royal Horticultural Society (1994), Flora: an Illustrated History of the Garden Flower (2001), The Royal Horticultural Society: a History 1804-2004 (2004), and most recently, RHS Chelsea Flower Show: a Centenary Celebration (2013). A former editor of Garden History, he is currently editor of Occasional Papers from the RHS Lindley Library.

He is a member of the Victorian Society's Buildings Committee, and for 25 years was a member of the Historic Parks and Gardens Committee/Panel of English Heritage. The RHS was founded in 1804, and is the world's largest gardening charity, inspiring passion and excellence in the science, art and practice of horticulture.

Alan Powers is a widely published author specializing in 20th-century art and design, with an interest in expanding the canon and reshaping the interpretation of Modernism, especially in the British context.

He has taught in several university schools of architecture, and has been active as an exhibition curator, conservationist and journalist. He has written a number of books on Ravilious including Ravilious and Co published by Thames & Hudson Ltd.

John Simpson has been the BBC's World Affairs Editor for more than half his fifty-two year career. In his time with the BBC, he has reported on major events all over the world, and was made a CBE in the Gulf War honours list in 1991. He has twice been the Royal Television Society's Journalist of the Year, and has won three BAFTAs, a News and Current Affairs award and an Emmy. He lives in Oxford.