The article presents proceedings of the Annual meeting of the Phycological Society of America at the University of Massachusetts, Amherst, Massachusetts, held between June 17-22, 1973. All sessions of the program at which contributed papers were presented are joint sessions of the Phycological Society of America and the Phycological Section of the Botanical Society of America. Various topics were covered in different sessions. Session one was on Taxonomy and Morphology while sessions two was on Physiology and Biochemistry.