This book contains selected works on the biomechanics of the hand accumulated in the Biomechanics Laboratory of Mayo Clinic over the past eleven years. It attempts to apply a composite approach to normal and pathological functions of the hand by utilizing mechanical modeling, anatomical testing and clinical verification. A collaborative effort of the disciplines of orthopedics and engineering science has been put forward in this research. Attention is focused on the understanding of the function of the hand in relation to force and motion potentials observed in normal and pathological cases.