Guy Messenger lived at Uppingham in Rutland, teaching biology at Uppingham School until his retirement in 1980. He remained an active botanist until his death, publishing a monograph on the flora of Rutland in 1971 and several contributions to Watsonia, the scientific journal of the Botanical Society of the British Isles. 

He was an early member of the Charles Close Society, joining in 1981, and quickly turned the analytical and classification skills he had acquired as a botanist to his new passion of cartobibliography. He was the author of the first full length monograph on a twentieth century map series, the Ordnance Survey one-inch map of England and Wales Third Edition (Large Sheet Series), which the CCS published in 1988. Guy was made an Honorary Member of the Charles Close Society in 1991. Further details of his life and work appear in the obituary in Sheetlines 38. 

Guy's maps and research papers were left to Cambridge University Library; the important pre-war maps are listed in a catalogue that may be viewed in the Map Department. His research papers have now been listed as a section of the Charles Close Society Archives 

Among these may be found his correspondence (1982-1993) with Richard Oliver, wherein many themes in the largely unexplored territory of Ordnance Survey research, much of which would evolve into the published work of both men, were developed. 

See also Guy Messenger, ‘What happened at Hendon Central in 1941?’, Sheetlines 32 (1992)