Doppler shift laser fluorescence spectroscopy (DSLFS) has been developed in the last few years as a powerful tool to measure densities and energy distributions of neutral particles. Its main application described in this paper is the study of particles ejected from surfaces under impact of atoms, ions or electrons. Complications and controversies in the interpretation of DSLFS spectra will be discussed. The major achievements and applications of the method over the last few years will be presented. One of the most important results has been a deeper insight into the composition of the particle fluxes ejected from surfaces under ion beam bombardment in respect to the degree of surface oxidation. This has been possible due to the fact that DSLFS enables us to measure the densities and energy distributions of neutral particles in specific electronic states. As a direct consequence, a large amount of information on sputtered excited atoms has recently been obtained by DSLFS.