Almost all present-day psychology textbooks begin their project either explicitly or implicitly discussing the nature of men and women and what there is about them as living, sentient beings that can indeed be studied systematically. Our discussion will also begin in this fashion by comparing the foundation which underlies mainstream psychology with that of the existential-phenomenological approach. As you know, psychology, as it is typically presented, is heavily indebted to the natural sciences both for its understanding of human phenomena and its methods. The ground or foundation for psychology offered in the present volume is existential-phenomenological philosophy, and whereas this particular philosophy has a long history, it is only in recent times that systematic attention has been given to its implications for psychology. Many of you will undoubtedly find some of the ideas introduced to be quite new and, more than likely, somewhat discordant with your presently held views.