ICG

ICG may refer to
 * ICG Communications
 * Illinois Central Gulf Railroad
 * Impedance cardiography, a hemorheology technique for detecting the properties of the blood flow in the thorax
 * Incitement to commit genocide
 * Indian Coast Guard
 * Icelandic Coast Guard
 * Indocyanine green
 * Institute of Cosmology and Gravitation, University of Portsmouth, England
 * Intelligence Collection Group, part of the United Kingdom's Defence Intelligence Staff
 * Intermediate Capital Group, a private equity and mezzanine capital firm based in London
 * International Children's Games, an International Olympic Committee-sanctioned sport event held every year
 * International Coal Group
 * International College for Girls, former name of IIS University
 * International Crisis Group, a non-profit organisation
 * Internet Capital Group
 * Inversive congruential generator
 * Intra-character gap (or inter-character gap) in American Morse code
 * Irish Continental Group, an Irish sea shipping firm
 * Independent Comics Group, an imprint of Eclipse Comics
 * International Committee on Global Navigation Satellite Systems (ICG) by United Nations Office for Outer Space Affairs
 * International Composers' Guild
 * International Cinematographers Guild
 * Integrated clock gating, in logic chips