The Commission

The Commission is made up of the five original Cosa Nostra families in Liberty City in Grand Theft Auto IV. The Commission is the Mafia families' means of discussing any problems between them; their meeting place is in Little Italy, Algonquin. During GTA IV, the Alderney based Pegorino Family are trying to gain a place on the Commission (by, for example, granting favors to the Pavano Family and waging a low-scale war against the Ancelotti Family), but they are apparently looked down upon by the existing five Liberty City families, and their ascension to Commission status seems unlikely, particularly after the events of GTA IV. They carry Pistol's, Combat Shotgun's, and SMG's and are tough when fighting on the streets.

The Families

 * The Gambetti Family. Led by Jon Gravelli


 * The Pavano Family. Led by Mary Valvona


 * The Messina Family. Led by Harvey Noto


 * The Lupisella Family. Led by Mark Lupisella


 * The Ancelotti Family. Led by Giovanni Ancelotti

The Rankings

 * Don (Boss)
 * Underboss
 * Consigliere (Adviser)
 * Caporegime (Captain)
 * Soldato (Soldier)
 * Mafia Enforcers
 * Associates

Weapons
The gang carries pistols, shotguns, submachine guns, knives and otherwise fight with their fists. The mobsters usually carry one or two weapons during gameplay as noted from Grand Theft Auto IV, its Episodes, and Grand Theft Auto: Chinatown Wars.

New York City Commission
The Commission in GTA IV is based on New York City's real Mafia Commission: The five families in New York City's Commission are:
 * The Bonnano family
 * The Colombo family
 * The Gambino family
 * The Genovese Family
 * The Lucchese family

Trivia

 * The Gambetti-Ancelotti rivalry is possibly based on the Gambino-Colombo war, as they are the only two families in the New York City Commission that are not allied with each other.
 * In the The Lost and Damned, before you fight them in Gang Wars, Clay will sometimes say "Lets teach those Mobsters it ain't the 70's anymore".
 * There is an easy way to tell if a pedestrian in Little Italy is in the Mafia by pushing them (this will result in them fighting back), then pull out a gun, they will take out either an SMG, Combat Shotgun, or Pistol.