Letter to Nicholson regarding arrangements for him to meet Casey's father, Lord Casey, in Australia, and related letter from Lord Casey to Donn Casey.

Correspondence related to environmental conferences and other matters, with one later letter to Nicholson, 1997, regarding a biography of Casson.

Chiefly Earthwatch Europe correspondence etc regarding the Prince's support for the organisation, including a reception at Highgrove, Jun 1993.

Undated manuscript draft of letter by Nicholson to Clapham; correspondence with A.J. Willis regarding Nicholson's assistance with the latter's article on Clapham for Biographical Memoirs of Fellows of the Royal Society, Vol.39, (Feb 1994), with Nicholson's typescript note on Clapham.

Brief correspondence regarding arrangements for meetings on population issues etc.

Correspondence regarding development of material for guidance on the visual aspects of environmental pollution.

Correspondence regarding general conservation matters including IUCN, WWF etc, 1956-1981; included is correspondence between Nicholson and Coolidge's wife, Martha, after her husband's death in 1985.

Letter to Nicholson regarding survey of learned and professional societies in the UK, with related paper.

Personal letters to Nicholson regarding various matters.

Correspondence chiefly regarding political topics, 1938-1950, including some related to a conference of MPs and economists (including Nicholson) held at Faringdon, 24 Sep 1948; correspondence (1988) with Anthony Howard, Deputy Editor of The Observer, with notes by Nicholson, regarding his assistance with Howard's biography of Crossman (this correspondence was initiated by a complaint by Nicholson to The Observer). Correspondents...

Personal letters to Nicholson, with one to Nicholson's brother; correspondence regarding Crouch's death and typescript of the obituary by Nicholson.

Brief correspondence regarding Crowther's appointment to the Royal Commission on the Constitution.

Typescript of Nicholson's obituary of Delacour published in British Birds, vol.79, no.3, Mar 1986, and cutting from offprint; related letter from British Birds.

Personal correspondence.