This book contains the refereed contributions from the 42nd annual meeting of ISOTT. The annual meetings of ISOTT bring together scientists from various fields (medicine, physiology, mathematics, biology, chemistry, physics, engineering, etc.) in a unique international forum. ISOTT conferences are a place where an atmosphere of interaction is created, where many questions are asked after each presentation and lively discussions occur at a high scientific level. This vivid interaction is the main motivation for members to participate and gain new ideas and knowledge in the broad field of oxygen transport to tissue. The papers in this volume summarize some of the outstanding contributions from the 42nd annual meeting, which included sessions on: cellular hypoxia and mitochondria; blood substitutes and oxygen therapeutics; oxygen transport in critical care medicine and disease; muscle oxygenation; multi modal imaging techniques; brain oxygenation and imaging; optical techniques for oxygen measurement; microcirculation; mathematical modelling of oxygen transport; and cancer metabolism.