Both pattern recognition and signal processing are rapidly growing areas. Organized with emphasis on many inter-relations between the two areas, a NATO Advanced Study Institute on Pattern Recognition and Signal Processing was held June 25th - July 4, 1978 at the E.N.S.T. (Department of Electronics) in Paris, France. This volume is the Proceedings of the Institute. It contains what I believed to be a truly outstanding collection of papers which cover all major activities in both pattern recognition and signal processing. The papers are grouped by topics as follows: I. Syntactic Methods: paper numbers 1, 2. II. Statistical Methods: paper numbers 3, 4, 5, 6. III. Detection and Estimation: paper numbers 7, 8. IV. Image Processing, Modelling, and Analysis: paper numbers 9, 10, 11, 12. V. Speech Application: paper numbers 13, 14. VI. Radar Application: paper number 15. Seismic Application: paper number 16. VII. Biomedical Application: paper numbers 17, 18, 19. VIII. IX. Reconstruction From Projections: paper numbers 20, 21- X. Signal Modelling and Application: paper numbers 22, 23, 24. XI. NATO Pattern Recognition Research Study Group Report: paper number 25. It is my strong belief that there is a need for continuing interaction between pattern recognition and signal processing. The book will serve as a useful text and reference for such a need, and for both areas. Finally on behalf of all participants of the Institute, I would like to thank Drs. T. Kester and M. N. Czdas of NATO for their support.