In North America, the Institute for Christian Studies (ICS) was established in Toronto to offer graduate degrees. The ICS has had a long cooperative relationship with the VU, the University of Toronto's federation of Theological Schools, and more recently also the University's Faculty of Philosophy. Thus, in North America, there is an active second generation of reformational philosophers in Calvin Seerveld; a third generation including Hendrik Hart, Bernard Zylstra (deceased), James Olthius, Arnold DeGraaff (afterward a practicing psychotherapist for 30 years and co-founder of Mono Therapy Center, Mono, Ontario), Thomas McIntire, Albert M. Wolters, William Rowe, George VanderVelde (a theologian who took his doctorate under G. C. Berkouwer); and fourth-generationers Paul Marshall and Robert Sweetman may be added – to name just those who have had active professorial roles at ICS.