The Timberline Symposium on Epithelial Cell Biology was established in 2002 to provide a forum for sharing the most recent developments in the field in an intimate and casual setting. Since its inception, one of the goals of the symposium has been to promote the intellectual interaction between expert established scientists and other attendees, including graduate students and postdoctoral fellows. The venue for the symposium, historic Timberline Lodge on Mount Hood, Oregon, provides both seclusion and excellent facilities for moderately sized groups. The focus of the symposium for 2005 will be """"""""Keratinocyte Stem Cells: tissue regeneration, wound healing and environmental responses"""""""" and will be devoted to the biology and pathology of keratinocyte stem cells and their progeny. There will be 18 speakers, all internationally recognized as leaders in their respective fields (8 American, 9 European, and 1 Australian scientist) and approximately 70 other conferees expected to include, as in previous years, senior graduate students, postdoctoral fellows and established scientists from academics and industry. Recent advances in the mechanisms of cell aging, wound healing, apoptosis, keratinocyte stem cell formation during development and the plasticity and signaling mechanisms that drive their differentiation into the various stratified squamous epithelial tissues (including epidermis, hair, oral mucosa, corneal and cervical epithelia), and tissue engineering using keratinocyte stem cells serve to make the subjects and speakers of this symposium especially timely. The meeting will commence on Saturday evening, February 5, 2005 with two keynote speakers who will introduce the topic area for the symposium. There will be four additional scientific sessions (two each on Sunday and Monday) for a total of 18 speakers. In addition to the five platform sessions, it is expected that 30-40 attendees will present posters. Posters will be available for viewing all day Sunday and Monday with a formal poster presentation session on Sunday evening.