This text is written by researchers at BT Laboratories and at universities who have investigated a set of problems in vision, speech and natural language. It presents a diversity of approaches to the solution of these problems, based on a range of neural network paradigms. The book also includes sections on implementation, which discuss some approaches to hardware realization; and architectures, which describe new ideas and algorithms. The findings discussed here should be of interest not only to those working in the applications areas discussed, but also to people working more widely in the field of neural networks. This book should be of interest to working researchers and graduate students in neural networks.