The Meyerhof Symposium on "Molecular Bioenergetics and Macromolecular Biochemistry" took place in Heidelberg from the 5th to the 8th of July, 1970. The timing was chosen to coincide with the creation of a new chair, in the Weizmann Institute of Science in Rehovot, in memory of OTTO MEYERHOF and the location was determined by the fact that so much of MEYERHOF'S scientific work was done in Heidelberg. The historical reason for the symposium was the urgent want of many leading biochemists and physiologists active in Molecular Biology to honour the memory of one of the greatest scientists in this field and also one of the greatest biologists of the 20th century. October 1971 is the twentieth anniversary of the death of OTTO MEYERHOF and 1972 marks 50 years since he was awarded the Nobel prize (1922). With regard to the age of some of his friends and pupils it was decided the symposium to be arranged in 1970, the first of the three commemorative years.