Ephraim R. McLean (born January 7, 1936) is an American organizational theorist, and Regents' Professor (Emeritus) of Information Systems and holder of the G.E. Smith (GRA) Eminent Scholars' Chair at the J. Mack Robinson College of Business. Known as one of the founders of the MIS discipline in the 1960s, his work with William H. DeLone on the information systems success model[1][2] is world-renowned.