Organized crime in Liberty City has traditionally been controlled by the Five Families (Gambetti, Pavano, Lupisella, Messina, and Ancelotti families) with the less influential Alderney Mob. Business interests range from all reaches of crime, murder, contract killing, bombings, extortion, loan sharking, racketeering, gambling, hijacking among many others. Within Liberty City are many people and activities linked to the Mafia. Over the years in Liberty City the mafia has come into conflict both internally amongst the families and with other criminal organizations throughout the city oftentimes resulting in war.
- In GTA: San Andreas all gangs have 3 models of gang members but the Mafia have 4 instead of 3.
- In GTA San Andreas one of the Mafia members would often comment about his appetite and gluttony.
- In GTA San Andreas, there is code in the game that shows the Mafia was able to own brown-colored turfs. They can still be made visible by using the Territory Glitch which may cause them to appear at random spots on the map. To be able to choose where their turfs are located, one could use Modifications such as a Save Game Editor or CLEO Modification. The Mafia patrol their turfs driving Admirals, Sentinels and Feltzers. As weapon, they use Knives, Desert Eagles and AK-47s.
- In most games, the mafia families often appear as an antagonistic gang toward the protagonist, with the exception of Leone Family in GTA San Andreas and Liberty City Stories, and The Commission in Grand Theft Auto IV, which all of them were neutral gangs.
- Grand Theft Auto: Liberty City Stories is the only game which the player works for the mafia in the entire storyline, the Leone Family.
- The Italian Mafia is easily the most powerful gang in Liberty City, even surpassing the heavily armed Russian Mafia, having the largest amount of members and being very well armed, but not as well the Russian Mafia though. They are much better with their weapons, being surgically precise at almost any range. They are also better at fighting and in combat.