This volume is a compilation of the presentations of the 6th International Plant Cold Hardiness seminar at the Unitas Congress Center in Helsinki, Finland, held 1st-5th July, 2001. The overall goal of the volume is to acknowledge the research findings and to provide a pivotal resource for scientists and researchers actively engaged in studying plant freezing and chilling stress. Chapter authors are researchers who have had significant contribution to the knowledge of plant cold hardiness.