Cosa Nostra

American criminal organization

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July 21, 2026

Quick Summary

Cosa Nostra, an Italian phrase meaning "our thing," refers to the Sicilian Mafia and its counterpart in the United States. This is a hierarchically structured criminal organization primarily composed of individuals of Italian or Sicilian descent.1

The American Mafia, also known as Cosa Nostra, is organized into several "families," with five major ones historically dominating New York City: the Bonanno, Colombo, Gambino, Genovese, and Lucchese families. These organizations engage in illegal activities such as gambling, labor racketeering, loan-sharking, and narcotics distribution.23

The origins of the Mafia can be traced back to 19th-century Sicily, possibly stemming from private armies hired to protect estates. Over time, these groups evolved into a powerful criminal society operating under a strict code of silence known as omertà. By the early 20th century, many mafiosi had emigrated to the United States, establishing similar criminal patterns. While their power has diminished due to law enforcement efforts and internal conflicts, the Mafia continues to operate.143

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Mafia
The 20th century and the Five Families
…organization had adopted the name Cosa Nostra [Italian: “Our Affair”].) From the 1950s, Mafia operations were conducted by some 24 groups, or “families,” throughout the country. In most cities where syndicated crime operated, there was one family, but in New York City there were five: Gambino, Genovese, Lucchese, Colombo, and…
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…organization had adopted the name Cosa Nostra [Italian: “Our Affair”].) From the 1950s, Mafia operations were conducted by some 24 groups, or “families,” throughout the country. In most cities where syndicated crime operated, there was one family, but in New York City there were five: Gambino, Genovese, Lucchese, Colombo, and…
Read More

Joseph Valachi
…called the Mafia—what Valachi termed Cosa Nostra (“Our Thing”). Robert Kennedy called his testimony the “biggest single intelligence breakthrough yet in combating organized crime and racketeering in the United States.” Investigations, indictments, and convictions followed Valachi’s testimony.
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…called the Mafia—what Valachi termed Cosa Nostra (“Our Thing”). Robert Kennedy called his testimony the “biggest single intelligence breakthrough yet in combating organized crime and racketeering in the United States.” Investigations, indictments, and convictions followed Valachi’s testimony.
Read More