IEP may refer to: Science and technology Immunoelectrophoresis Inclusion–exclusion principle Integrated electric propulsion Isoelectric point Education and research Individualized Education Program, in the United States Instituts d'études politiques (Institutes of Political Studies) Institute for Economics and Peace Institute for European Politics Institute for Political Studies – Catholic University of Portugal () Internet Encyclopedia of Philosophy Other uses Icahn Enterprises, an American conglomerate Institute of Employability Professionals, a British professional association Intercity Express Programme, a British rail transport initiative Irish pound