Ailsa Giles Maxwell (née Macdonald; 16 December 1922 – 10 February 2020) was a British Bletchley Park code breaker and historian.

[2] After completing the first year of her economics degree with distinction, Maxwell planned to join the WRENS, however she was approached by the Foreign Office in the summer of 1943, and invited to interview for an unspecified job.

[7] Maxwell was responsible for compiling menus from information obtained by other huts and inputting it to the electro-mechanical codebreaking Bombe,[5] as part of the effort to decipher the Germans' Enigma code.

[5] She was required to sign the Official Secrets Act and did not speak about her experiences until some time after the work of the code-breaking operation was declassified in 1974.

She also undertook a number of research projects with her husband, including the history of Scottish silversmiths and goldsmiths, and together they translated the diary of George Home (1660-1705) from Berwickshire.

[3] Maxwell's war-time experiences at Bletchley Park, partially inspired the novel The Amber Shadows by Lucy Ribchester.