Caporegime is a captain of a mafia family that runs crew of solders.though its a high rank,the other 2 higher rankings is Underboss (which is next in line to be the Don) and Don (which is the leader of a mafia family.
Notable caporegimes include Toni Cipriani and Vincenzo Cilli of the Leone Family.Toni Cipriani was a capo sometime before 1994 when he was called out by Don Salvatore Leone to kill a made man (unknown from which family but has to be either the Forelli Family or Sindacco Family.) After Toni killed him he was told to lay low which made Cilli to climb up the ranks and take over Cipriani's regime.By the time Cipriani came back to Liberty City he was put back as a low level goon working at Cilli's regime.
Vincenzo was always making Toni work and enjoyed pushing him around,sometime after Toni quites doing jobs for him.When Toni was gaining Don Leone's trust again Cilli gives Cipriani a call to tell him to meet him at the docks at Portland Harbor which was a trap and many of Cillis solders attacked Cipriani but he managed to kill them all,and killed Cilli himself.
By the end of 1998 Toni took over his old regime and started to make people do work for him and not do it himself.