The Adventure of the Naval Treaty is a short Sherlock Holmes story penned by Sir Arthur Conan Doyle. Conan Doyle, in this story, has the world famous consulting detective delving into the world of international espionage, for Holmes is tasked with securing the return of a vital Naval Treaty.

The case sees Sherlock Holmes dealing with high political and international intrigue, but at the same time Holmes is arguably more worried about the reputation of his client, Percy Phelps is being questioned.