Benjamin "Lefty" Ruggiero was an American mobster in the Bonanno crime family. He is well known for his friendship and mentorship of FBI undercover agent Joseph D. Pistone, who Ruggiero knew as Donnie Brasco. When Pistone's operation was ended on July 26, 1981, the FBI intercepted and arrested Ruggiero on August 29, 1981. In November 1982, Ruggiero was sentenced to 15 years in prison for racketeering conspiracy; he was released in April 1993 before his death from cancer.

The Bonanno crime family is an Italian-American Mafia crime family and one of the "Five Families" that dominate organized crime activities in New York City, and in the United States, as part of the criminal phenomenon known as the American Mafia.