ISAC

ISAC may refer to:

• internet Speech Audio Codec (as "iSAC"), a wideband speech codec
• Institute for the Study of American Cultures, a defunct organization devoted to the study of pre-Columbian contact between the Old and New Worlds
• Institute for the Study of Ancient Cultures, West Asia & North Africa, a multidisciplinary research center at the University of Chicago
• Information Sharing and Analysis Center, a cybersecurity non-profit organization
• Indian Space Research Organisation Satellite Centre, the lead ISRO centre for technology testing and spacecraft assembly integration in India
• Immune stimulating antibody conjugate, a monoclonal antibody
• Idol Star Athletics Championships, Korean biannual Athletics gathering