The Second Conference of the International Society of Hemorheology took place under the auspices of the University of Heidelberg from July 27 - August 1,1969 in Heidel berg. At this conference the name of the Society was changed to THE INTERNA TIONAL SOCIETY OF BIORHEOLOGY, since the members decided to enlarge the scope of the Society to include all fields of biorheology. Meanwhile the Society has become an Affiliated Commission of the International Union of Pure and Applied Biophysics. The abstracts of the scientific papers, as they appeared in the program of the Confe rence, have been reprinted in BIORHEOLOGY (volume 6, No.4, April 1970). This international journal has become the official organ of our Society. We are greatly indebted to the Honorary Chairman, Professor G. QUADBECK, Dean of the University of Heidelberg Medical School, who gave substantial aid to one of us (H. H. H.), the Conference Chairman, in organizing this international meeting. We are grateful to the Mayor of the City of Heidelberg who welcomed the participants and their families in the Cellar of the Great Barrel of the Heidelberger SchloB. We thank the members of the Ladies' Committee, Mrs. IRMGARD QUADBECK, Mrs. ELISABETH HARTERT and Mrs. KARIN KREITER, who arranged a most successful social program in Heidelberg and the romantic Neckar valley."