On 4 March 2019, Diplo published G.R. Berridge’s e-book, ‘Diplomacy and Secret Service‘. This historically grounded work considers key questions on the contemporary interface between diplomacy and the secret service. The book is part of the Invitations to Diplomacy series, launched to provide authors with the opportunity to publish introductory works on any important diplomatic subject, and to make them as accessible as possible in terms of style, cost, and electronic format.