The Plombières Agreement (Italian: Accordi di Plombières, French: Entrevue de Plombières) of 21 July 1858 was a secret verbal agreement concluded at Plombières-les-Bains between the chief minister of Piedmont-Sardinia, Count Cavour,[1] and the French Emperor, Napoleon III. Some older English language sources refer to it as the Treaty of Plombières, but most avoid identifying it as a "treaty".