We have developed a comprehensive modelling network for glow discharge plasmas used for analytical spectroscopy in order to obtain better insight into the plasma characteristics that are desirable for good analytical practice. The modelling network consists of Monte-Carlo, fluid and collisional-radiative models, as well as a heat transfer model and a computational fluid dynamics code, to describe the behaviour of the various plasma species. Typical calculation results include the electrical characteristics (current, voltage, pressure relations), the electric field distribution, the densities, fluxes and energies of the various plasma species, information about the various collisions in the plasma and about cathode sputtering, optical emission intensities, etc. In this paper we focus on results that are of direct analytical interest, such as crater profiles and erosion rates due to sputtering, implantation profiles, glow discharge source design, optical emission intensities and the effect of hydrogen addition.