This volume contains those papers which were presented at the Second International Symposium on Oxygen Transport to Tissue, together with the discussion which followed. These discussions were generously summarized by the chairman of the various sessions. This symposium in Marinz was the third international meeting, after those held in Dortmund in 1971 and Charleston--Clemon in 1973, which dealt primarily with problems relating to oxygen transport to thissue under physiological and pathophysiological conditions. It was the second symposium conducted by the International Society on Oxygen Transport to Tissue which was founded in 1973.