This book constitutes the proceedings of the Fourth International Workshop on Mul timedia Information Systems (MIS 98) held in Istanbul, Turkey in September 1998. This workshop builds upon the success of the three previous workshops in this series that were held in Arlington, VA, West Point, NY, and Como, Italy. As in the past, this is a small focused workshop, consisting of participants drawn from a wide variety of disciplines (e. g. theory, algorithms, real time systems, networks, operating sys tems, graphics and visualization, databases, artificial intelligence, etc. ), all of which focus...