After the explosion of research on neural networks in the eighties, the nineties have seen a boom in industrial applications of neural networks. In contrast to the large output of publications in international neural network journals, which reflects the increase in neural network research, the large number of successful applications are less accessible. To make a survey of successful applications in industry in Europe, a project called SIENA was initiated with support from the European Community. The aim of SIENA was to assess the business impact of neural networks. Data were collected on both the supplier side and the end-user side of the market. In addition, case studies of successful ''money-making'' applications using neural networks were gathered. This book contains detailed descriptions of some of the applications.