The author does not over-estimate the importance of this little book: it is nothing more than its title claims. It consists of three lectures given to popular audiences. It represents, however, a considerable amount of work in an almost virgin field. It has involved hard journeys to remote mountain monasteries, and days and nights of conversation and inquiry with many monks and priests. It is not, however, a profound study nor an exhaustive presentation. It barely touches many a subject, which would alone furnish more material than could be treated in three such lectures. It but scratches the surface. The material which it presents is however new. Outside of Mrs. Bishop's account of her visit to the Diamond Mountain monasteries and scattered references in viii her book to a few local temples, there is almost nothing on the subject of Korean Buddhism accessible to English readers. A glance at our bibliography will show that not one of the books or articles there listed appeared in the West. All were printed at Seoul, Shanghai and Tokyo and publications appearing at those centers are little known outside. To aid serious readers, who may care to secure them, the publishers' names are given in our list. The author has carefully read all the items listed and acknowledges indebtedness to all the authors.