Principles and Instrumentation.- Photon Migration in Tissue.- Photon Migration in NIRS Brain Imaging.- Clinical Application of NIRS.- In-Vivo NIRS and Muscle Oxidative Metabolism.- Intracellular Oxygen Dynamics Observed by NIRS during Skeletal Muscle Contraction.- Muscle Oxygen Saturation Measurements in Diving Mammals and Birds Using NIRS.- Noninvasive NMR and NIRS Measurement of Vascular and Intracellular Oxygenation In Vivo.