Founded in 1924 by Dean Leroy Allen of Southwestern College and Dean William A. Hamilton of the College of William and Mary, Pi Gamma Mu was intended to provide an honor society that would foster cooperation among the various social science disciplines. At that time, many new disciplines were emerging, including social work, international relations, criminal justice or criminology, and human geography. There were also noticeable methodological shifts in favor of what the founders of Pi Gamma Mu called “sheer quantification” and “mensuration” (i.e., statistical parameters) in many of the older disciplines. Pi Gamma Mu was an early advocate of an interdisciplinary approach to achieve “integration” and “humanization” in the study of social problems. Its leaders called for the “reintegration of the several social sciences into a philosophy of society.” In December 1924, 17 new chapters were organized simultaneously, mostly in liberal arts colleges and universities. The chapters at Columbia University (1925) and the University of Pennsylvania (1927) were among the first to be chartered in large universities. The quarterly journal, Social Science, was first published in November 1925 to carry out the mission of Pi Gamma Mu. As its subtitle indicated, the journal was a forum “for the scientific study of social problems” and to “promote cooperation” among its member-disciplines. Pi Gamma Mu was incorporated in 1929 as a non-profit educational corporation. The 1920s and 1930s was a period of heightened growth for Pi Gamma Mu. The first chapter outside of the continental United States was installed at the University of Hawaii in 1929. Three years later, chapters were organized at the University of Toronto in Canada and the University of the Philippines. A charter was granted in 1955 to the Catholic University of Puerto Rico. To recognize its overseas chapters, Pi Gamma Mu became officially the “international honor society in social sciences” in 1982. That same year, Social Science was renamed International Social Science Review. It remains a distinguished peer-reviewed and indexed journal with an interdisciplinary approach to the social sciences. In over eight decades of existence, Pi Gamma Mu has produced many notable alumni. These include a U.S. president (Lyndon Baines Johnson), a prime minister of Canada (Lester B. Pearson, also a Nobel Peace Prize winner), two Philippine presidents (Jose P. Laurel and Ferdinand E. Marcos), one president of Panama (Dr. Ricardo Alfaro Jovean), leading American anthropologist Margaret Mead, sociologists Pitirim Sorokin and Charles A. Ellwood, criminologist Edward Ross, internationally acclaimed cardiologist Philip Ernst Boas who invented the cardiotachometer, incumbent U.S. senator Charles Grassley of Iowa, incumbent Colorado congresswoman Diana DeGette, deputy whip of the U.S. House of Representatives, and prominent lawyer and former U.S. attorney–general William French Smith. Today, Pi Gamma Mu has active chapters in over 160 colleges and universities. Its total membership exceeds 230,000.