This series consists of the files and papers of the Central Defence Scientific Staff, set up under the unified Ministry of Defence, together with papers inherited from its predecessors in the smaller, pre-1964, Ministry of Defence. They include papers of the Chief Scientific Adviser, his assistant for nuclear matters and papers relating to atomic energy intelligence.
As well as registered files of the Chief Scientific Adviser (in the CSA series), the series includes unregistered papers in branch folders from the Atomic Energy Intelligence Committee, the papers of the first Assistant Chief Scientific Adviser (Nuclear ), Dr Robert Press, inherited from his earlier work on the pre-1964 staff of the Chief Scientific Adviser,and later branch folders of ACSA (N).