This award supports the participation of eleven U.S. mathematicians in a small international symposium to be held in Iceland in July, 1990. The organizing committee, chaired by George McNulty of the University of South Carolina, has representatives from several countries. The local organizer is Professor Ragnar Sigurdsson, President of the Icelandic Mathematical Society. The meeting is co- sponsored by this Society as well as the University of Iceland and several U.S. universities. The purpose of the symposium is to provide an international forum for the exchange of ideas and results at the leading edge of mathematical research in lattice theory, universal algebra and algebraic logic. The occasion for the symposium is the seventieth birthday of Bjarni Jonsson, who was born in Iceland in 1920, though his academic training and career were pursued in the United States. His fundamental contributions in the above topics have made him a leading figure for nearly forty years. The present day vitality of universal algebra and of lattice theory can be traced, in large part, to new research directions initiated by Professor Jonsson. The areas addressed by the "Jonsson Symposium" are important mainstream fields of mathematics that have grown enormously in the past forty years; the main researchers in these fields are scattered around the world. Although these topics are addressed regularly at small national or regional mathematics meetings, this will be the first conference to bring together a substantial number of specialists from North America to meet their colleagues from Western and Central Europe. The symposium offers a strong program and a convenient central location that should attract broad international participation and provide a strong stimulus to cooperative research. NSF funding will be directed especially at the participation of young U.S. mathematicians.