The papers in this volume are from the workshop on Protein Flexibility and Folding held in Traverse City, Michigan from August 13-17, 2000. The purpose of the workshop was to bring together diverse people interested in protein folding and flexibility from theoretical, computational and experimental perspectives and to encourage discussion on new approaches and challenges in the field. The workshop was held in the Park Plaza Hotel with 43 participants, including 24 invited speakers. The small size of the group made for easy exchanges, and many of the presentations by the invited speakers appear in this volume. There was also a very lively poster session. The three-day workshop was organized so that the first day covered Flexibility and Dynamics, the second day Folding and Unfolding, and the third day Evolution and Design. This area of science is particularly appealing as it spans a range of questions from very fundamental - as to how proteins fold in such short times with such reliability - to applications such as the role of flexibility in screening for new ligands to a protein. Protein flexibility and folding have attracted the attention of scientists from many disciplines, ranging from mathematics to molecular biology. The scientists at the workshop represented the breadth of challenges in theory and applications that keep this field so fascinating and dynamic. The present volume is organized along these same lines.