IAPS: International Association for the Philosophy of Sport
IC: Inside Centre
ICC: Independent Citing Commissioner
ICF: International Canoe Federation
ICW: Independent Championship Wrestling
ICW: Insane Championship Wrestling
ICWA: International Championship Wrestling Alliance
IFL: Indoor Football League
IFL: Intense Football League
IGRAB: International Gay Rugby Association and Board
IHL: International Hockey League
IHRA: International Hot Rod Association
IMA: Ideal Mechanical Advantage
IMBA: International Mountain Bicycling Association
IMG: International Management Group
IOC: International Olympic Committee
IPWA: Independent Professional Wrestling Alliance
IRB: International Rugby Board
ISPW: Independent Superstars of Pro Wrestling
ISW: Incredibly Strange Wrestling
ITA: Intercollegiate Tennis Association
ITF: International Tennis Federation
ITHF: International Tennis Hall of Fame
ITOOTR: In the Opinion of the Referee
IWA: Independent Wrestling Association
IWA: International Wrestling Alliance
IWA: International Wrestling Association
IWC: International Wrestling Cartel
IWF: Impact Wrestling Federation
IWF: Independent Wrestling Federation
IWF: International Weightlifting Federation
IWFL: Independent Women's Football League
IWU: International Wrestling Union