You've got to be a hard arsed businessman, ruthless. The only qualification you need is a degree from the school of hard knocks. Unless you want to be a promoter like the UK's Frank Warren, in which case you will have to splice your DNA with that of a Woman's vagina. Seriously though, most promoters are fairly shady characters that would sell their grandmother to turn a buck, but most have a charisma that blinds you to their dark side (google Don King's past for a good example)