Best of Def Leppard (or The Best Of) is a compilation of some of Def Leppard's most popular songs. The album charted at No. 6 on the UK Albums Chart. Best Of supplements 1995's Vault as the definitive collection of Def Leppard's work. In fact, Best of Disc 1 is essentially Vault with the addition of "Long Long Way to Go. Best Of was released in a number of territories around the world, but not North America. A 2-CD best of called Rock of Ages was issued there instead.