As the range of people gaining access to information is widening a custom-made presentation of information is growing more and more important. This book presents an approach that allows a multimedia presentation system to cater for the users‘ needs. Susanne van Mulken discusses the relevant literature on cognitive psychology, current multimedia presentation systems, and user modeling, and she develops a system module which - on the basis of Bayesian networks - is able to estimate the decodability of planned presentations for an individual user. The module learns facts about the user by means of the interaction and diagnoses the critical parts of a display so that they can be remedied before the actual presentation. Selected models are empirically validated by psychological experiments.