Phi Kappa Psi (
ΦΚΨ,
Phi Psi) is an American collegiate social
fraternity founded in the southwest corner of the second floor of Widow Letterman's home on the campus of
Jefferson College in
Canonsburg, Pennsylvania on February 19, 1852. There are over 100 chapters and
colonies at accredited four year colleges and universities throughout the United States. More than 119,000 men have been initiated into Phi Kappa Psi since its founding. Phi Kappa Psi and
Phi Gamma Delta, both founded at the same college, form the
Jefferson Duo.