IEP
IEP may refer to:

Science and technology 
 Immunoelectrophoresis, biochemistry method 
 Inclusion–exclusion principle, in the mathematics branch of combinatorics 
 Integrated electric propulsion, in marine propulsion 
 Isoelectric point, the pH where a molecule is electrically neutral

Education and research 
 Individualized Education Program, in the United States, for children with disabilities 
 Instituts d'études politiques (Institutes of Political Studies), higher education institutions in France 
 Institute for Economics and Peace, a think tank
 Institute for European Politics, a Berlin research centre
 Institute for Political Studies – Catholic University of Portugal ()
 Internet Encyclopedia of Philosophy

Other uses 
 Icahn Enterprises, an American conglomerate
 Independent Expert Panel, concerned with misconduct by members of the UK parliament 
 Institute of Employability Professionals, a British professional association
 Intercity Express Programme, a British rail transport initiative
 Irish pound, the pre-euro currency of Ireland