This Symposium on Spectroscopic Light Sources was organized with the thought in mind that the time has arrived when the field of spectrochemical analysis can best be advanced by a detailed examination of its various subdivisions. The techniques and instruments used in spectrochemical analysis divide themselves more or less naturally into three groups having to do, respectively, with the excitation of the sample, the resolution of the spectrum, and the determination of the relative intensities of the light emitted at various wavelengths. It was thought by the committee that the first of these groups is perhaps the least advanced and that a detailed study in the form of a symposium might be a particularly desirable contribution at this time. It is realized of course that none of these particular problems can be divorced entirely from the over-all problem of correlating the observed intensity ratios with the actual composition of the sample. In this connection the question of sample history and preparation is of prime importance and might well be considered either as a separate topic or as a part of the larger subject of excitation. The first paper of the Symposium attempts to summarize present practice and to correlate it with the more detailed studies to follow. The second paper presents a detailed study of a particular kind of source. In the next paper spectroscopic sources are considered from the viewpoint of the physicist who has specialized in the study of electrical discharges in gases rather than from the viewpoint of the spectroscopist. The last paper gives results of a study by a unique method of various processes occurring in the discharge. Finally, a number of well known practicing spectroscopists have been asked to present discussions. These discussions are not limited to the contents of the principal papers and might be more correctly characterized as short contributions of interest in connection with problems of current practice.