The symposium "UV, Blue and Green Light Emission fromSemiconductor Materials" was part of the European MaterialsResearch Society (E-MRS) Spring Meeting in Strasbourg, 4-7 June,1996 and it was arranged to bring together specialists in growth,characterization and device fabrication of materials suitable forvisible and UV optoelectronic applications. Although the mainemphasis was on the development of semiconductor diode lasers,work was also presented on the progress of frequently doublingtechniques which have an immediate application in commercialsystems. The proceedings are divided into Part I and Part IIreflecting the two streams of research based on II-VIsemiconductors on the one hand and III-V GaN based semiconductorson the other hand. Although these two areas are competingvigorously for the realization of practical blue laser diodes,there are many common problems, particularly with doping and also the need for suitable substrates for the growth of latticematched structures.The invited talks were presented byspeakers from Japan, the USA and Europe with representation fromboth University and Industrial research groups. In particular,leaders in the development of blue lasers SONY (II-VI devices)and Nichia (GaN devices) provided important device papersalongside the excellent contributions on a wide range of topicscovering epitaxial growth, optical structural and electricalmeasurements as well as problems of compensation of dopants andlaser lifetimes.The symposium "Nonlinear Optical andOptoelectronics Organic Materials" dealt with the development oforganic molecules and polymers as potential replacements forexisting materials in electronic, optoelectronics and nonlinearoptical devices.