A knowledge of the distribution of stellar luminosities along the zero-age main sequence can be obtained by applying evolutionary theory to the observed luminosity function. Thus by allowing for the facts that the intrinsically brighter stars have evolved away from the main sequence and that the most massive stars have probably turned into white dwarfs, one may derive what is termed the initial luminosity function. Application of an appropriate mass-luminosity relationship readily turns the initial luminosity function into the initial mass function. Salpeter has carried out the above procedure for stars with 4