Abstract
A review of discharge lamp developments over recent years shows that a reiterative process takes place between advances in fundamental understanding of discharge phenomena and problems revealed as new lamps find practical application. These two aspects of discharge lamp development govern the evolution of new types of lamps and are considered for low pressure sodium lamps, high pressure sodium lamps, fluorescent lamps, high pressure mercury lamps and metal halide lamps. It is apparent that research is as active on well-established types of discharge lamps as on the newer types.