This volume contains the articles contributed to the Minnesota Con ference on Complex Analysis (COCA). The Conference was held March 16-21, 1964, at the University of Minnesota, under the sponsorship of the U. S. Air Force Office of Scientific Research with thirty-one invited participants attending. Of these, nineteen presented their papers in person in the form of one-hour lectures. In addition, this volume con tains papers contributed by other attending participants as well as by participants who, after having planned to attend, were unable to do so. The list of particip ants, as well as the contributions to these Proceed ings, clearly do not represent a complete coverage of the activities in all fields of complex analysis. It is hoped, however, that these limitations stemming from the partly deliberate selections will allow a fairly com prehensive account of the current research in some of those areas of complex analysis that, in the editors' belief, have rapidly developed during the past decade and may remain as active in the foreseeable future as they are at the present time. In conclusion, the editors wish to thank, first of all, the participants and contributors to these Proceedings for their enthusiastic cooperation and encouragement. Our thanks are due also to the University of Min nesota, for offering the physical facilities for the Conference, and to Springer-Verlag for publishing these proceedings."

This volume contains the articles contributed to the Conference on Categorical Algebra, held June 7-12,1965, at the San Diego campus of the University of California under the sponsorship of the United States Air Force Office of Scientific Research. Of the thirty-seven mathemati cians, who were present seventeen presented their papers in the form of lectures. In addition, this volume contains papers contributed by other attending participants as well as by those who, after having planned to attend, were unable to do so. The editors hope to have achieved a representative, if incomplete, cover age of the present activities in Categorical Algebra within the United States by bringing together this group of mathematicians and by solici ting the articles contained in this volume. They also hope that these Proceedings indicate the trend of research in Categorical Algebra in this country. In conclusion, the editors wish to thank the participants and contrib. utors to these Proceedings for their continuous cooperation and encour agement. Our thanks are also due to the Springer-Verlag for publishing these Proceedings in a surprisingly short time after receiving the manu scripts."