This book contains the proceedings of the 11 'h international symposium dedicated to the understanding of animal "Life in the Cold", held at Jungholz (Austria), August 13-18, 2000. In 55 chapters contributed by researchers from 16 countries the current state of knowledge is reviewed, and the most recent developments and discussions in this field are highlighted. The first symposium on hibernation and life in the cold was held in 1959, and from then on they continued to occur every 3-5 years. The regular occurrence of these meetings became almost a tradition. A tradition which is entirely based on the enthusiasm of participants, and was nourished by scientific progress in this area during the past decades. The first symposium in 1959 was organised by Charles P. Lyman and Albert R. Dawe and was almost entirely dedicated to hibernation and torpor. This has been a backbone topic of the following symposia, although other aspects of animal energetics, thermal physiology and biochemistry were included in later meetings.