IWG

IWG may refer to:


 * Inch of Water Gauge, pressure unit corresponding to 2.54 cmH2O or approximately 249 Pa
 * "I Wanna Go", song by Britney Spears
 * Interagency Working Group such as the
 * Nazi War Crimes and Japanese Imperial Government Records Interagency Working Group
 * Interagency Working Group on Youth Programs
 * IWG plc, a global provider of office space
 * Irish Workers' Group