New Laser Sources.- Progress in Laser Techniques: Toward Industrial U.V. Laser Tools for the Nineties.- X-Ray Laser World Wide Progress.- Electron Wiggling Influence on Optical Guiding in a FEL.- The Free Electron Laser: a Brief Analysis of Theory and Experiment.- Integrated High-Power-CO2-Laser with Coaxial Turbo-Blower and RF-Excitation.- Theoretical and Experimental Considerations.- Polarization and Nonlinear Propagation in Single-Mode Fibres.- Coupled-Cavity Effects in Semiconductor Lasers.- Problems of the Charge Collection in Laser Multiphoton Ionization Experiments.- National Programs.- Italian Programs for Laser Source Development and Applications.- Industrial Applications.- Lasers in Modern Industries.- Interaction of Pulsed Laser Beams with Solid Surfaces: Laser Heating and Melting.- Optical Design Considerations for CO2 Laser Industrial Systems.- Laser Diagnostics of Industrial Chemical Processes.- Lasers in Industrial Chemical Processes.- Lasers in Thin Films Deposition.- Biomedical Applications.- Fundamentals of Low-Power Laser Photomedicine.- Laser Applications in Bio-Medicine: Tumor Therapy and Localization Using Photosensitizing Drugs.- Fundamentals of Laser Angioplasty: Photoablation and Spectral Diagnostics.- Photons in Medicine.- Vasovasostomy by Means of a Nd:Yag Laser.- New Applications of Lasers.- Advances in Laser Fusion.- Non linear Laser Plasma Interactions with Applications to Elementary Particle Acceleration.- Lasers in Nuclear Physics.- Application of Laser Cooling to the Atomic Frequency Standards.- Digital Logic Elements for Optical Computing.- Investigation of Atmospheric Properties with Laser-Radiation.- Laser Techniques for Measuring Atmospheric Trace Constituents.

The conference "Laser Science and Technology" was held May 11-19, 1987 in Erice, Sicily. This was the 12th conference organized by the Internatio­ nal School of Quantum Electronics, under the auspices of the "Ettore Majorana" Center for Scientific Culture. This volume contains both the in­ vited and contributed papers presented at the conference, covering current research work in two areas: new laser sources, and laser applications. The operation of the first laser by Dr. Theodore Maiman in 1960 initia­ ted a decade of scientific exploration of new laser sources. This was fol­ lowed by the decade of the 1970s, which was characterized by "technology push" in which the discoveries of the 1960s were seeking practical applica­ tion. In the 1980s we are instead seeking "applications pull," in which the success and rapid maturing of laser applications provides both inspiration and financial resources to stimulate additional work both on laser sources and applications. The papers presented in these Proceedings attest to the great vitali­ ty of research in both these areas: New Laser Sources. The papers describe current developments in ultra­ violet excimer lasers, X-ray lasers, and free electron lasers. These new lasers share several characteristics: each is a potentially important coher­ ent source; each is at a relatively short wavelength (below 1 micrometer); and each is receiving significant development attention today.