Both of us were lucky indeed to have our research associate, Dr. Yvonne H oogeveen, to keep us on course and spend much time and effort on getting the text in optimal shape. Without her, it would have been dif? cult, if not imp- sible, to ensure the completion of this endeavour. To complicate matters further, we had a number of potential and agreed authors either dropping out due to illness or because of changes in empl- ment situations precluding them from contributing. Nevertheless, the result is a truly international effort that we are proud of. For this we wish to thank the co-workers of Springer-Verlag, as they were truly exemplary in their cooperation. Ursula Davis, in particular, deserves our thanks. Dr. Devos and I are extremely thankful to all the authors: you all are the book! They were selected for their prominence in their specialty, and the list of these authors represents a broad combination of experience, teaching ability and stature. Finally, it was a pleasure to contribute to better imaging in children, so- thing that pediatric radiologists of course have made their aim in life, but also should be aimed for by all radiologists in general.

Both of us were lucky indeed to have our research associate, Dr. Yvonne H oogeveen, to keep us on course and spend much time and effort on getting the text in optimal shape. Without her, it would have been dif? cult, if not imp- sible, to ensure the completion of this endeavour. To complicate matters further, we had a number of potential and agreed authors either dropping out due to illness or because of changes in empl- ment situations precluding them from contributing. Nevertheless, the result is a truly international effort that we are proud of. For this we wish to thank the co-workers of Springer-Verlag, as they were truly exemplary in their cooperation. Ursula Davis, in particular, deserves our thanks. Dr. Devos and I are extremely thankful to all the authors: you all are the book! They were selected for their prominence in their specialty, and the list of these authors represents a broad combination of experience, teaching ability and stature. Finally, it was a pleasure to contribute to better imaging in children, so- thing that pediatric radiologists of course have made their aim in life, but also should be aimed for by all radiologists in general.