Professor Ketelaar has lived in Japan off and on for fifteen of the last thirty-five years, mostly in Kyoto, but also in Tokyo, Hokkaidô (mostly during the summer), and Kyûshû (mostly during the winter). He did some of his undergraduate work at Waseda University and some of his graduate and dissertation work at Kyoto University.
He has taught in Japan as a study-trip leader for the Smithsonian Institution and the University of Chicago Alumni Association. He was an undergraduate educator for the Kyoto Consortium for Japanese Studies (KCJS) on three separate occasions, and in 2012, he led a group of University of Chicago undergraduates to Tokyo, Kyoto, Nara, and Osaka after a month studying Japanese history and culture with them at the university's Center in Beijing.
Professor Ketelaar was a member of the KCJS Governing Board for fifteen years and currently serves as the chair of the Executive Committee and the Governing Board of the Inter-University Center for Japanese Language Studies (IUC) based in Yokohama, Japan.