underboss

right|350px|thumb|Structure of Mafia crime family

Underboss () is a position within the leadership structure of certain organized crime groups, particularly in Sicilian and Italian-American Mafia crime families. The underboss is second in command to the boss. The underboss is also person-in-charge of all capos and their soldiers. The underboss is sometimes a family member, such as a son, who will take over the family if the boss is sick, killed, or imprisoned. However the position of street boss has somewhat challenged the rank of underboss in the modern era. The position was installed within the Genovese crime family since at least the mid-1960s. It has also been used in the Detroit crime family and the Chicago Outfit.