Since the beginning of the 1960s studies of periglacial phenomena and fossil periglacial land-forms in Japan have been carried out in areas from Hokkaido to Kyushu and from the high mountains to the piedmonts. In addition, Japanese investigations in the polar and sub-polar regions of the world have been accumulating steadily in the last five years. This symposium was organized to clarify the characteristics of periglacial environments in Japan present and past by means of discussion centering about the following two main themes: I. Present periglacial processes and environments in Japan and polar regions. Keynote reports: 1) N. Matsuoka: Mechanism and effect of frost action on periglacial landforms. 2) K. Hirakawa: “The morphogenetic system” under various periglacial environments. Short reports: 1) M. Fukuda, K. Shimokawa, N. Takahashi* and T. Sone: Permafrost in the vicinity of the Antarctic Peninsula. 2) S. Sawaguchi: Relation between frost action and mass-movement. 3) H. Tabuchi* and Y. Hara: Periglacial environment and phenomena in Finnish Lapland. II. Problems on fossil periglacial slopes in Japan. Keynote reports: 1) O. Yanagimachi: Vertical variations in morphogenetic zones for periglacial smooth slopes and estimation of air temperatures in the last glacial maximum from these variations. 2) Y. Ono: Present and last-glacial periglacial belts in Japan. Short reports: 1) H. Hasegawa: On the characteristic features of periglacial smooth slopes based on airphoto interpretation. 2) T. Sugai: Periglacial slopes and erosional low-relief surfaces in the Akaishi Mountains, Central Japan. 3) K. Mizuno: What are the factors controlling invasion and stabilization of vegetation on a periglacial smooth slope? 4) C. Shimizu: Vertical distribution of periglacial slopes in the last glacial period and its relation with distribution of Pleistocene volcanic ashes. 5) S. Tanaka* and R. Nomura: Colluvial slopes and block streams in the eastern Chugoku Mountains, western Japan. 6) T. Oguchi: Factors for formation of periglacial landforms in lowlands of western Japan. 7) K. Yamamoto: Periglacial slope deposits with special reference to identification by macro fabric analysis.