From the contents: Gallium-nitride versus zinc-selenide lasers: a real issue? - Progress and prospects of Group III nitride semiconductors. - Recent progress in epitaxial lateral overgrowth techniques for growing bulk GaN by HVPE. - MBE growth and device chracterization of Be-based materials for application to blue-green laser diodes. - The effects of isoelectronic in-doping in GaN films grown by MOCVD.