During xerographic development, charged toner particles are removed from the developer by the latent electrostatic image, and are replaced by uncharged dispensed toner particles. As a result, the total toner population in a developer contains charged incumbent particles and uncharged added particles. To maintain image quality, the latter toner particles must rapidly chargeequilibrate with the already-charged toner particles in the developer. As outlined in the present paper, a conceptual chargeadmix model based on a direct graphical analysis can provide a clear picture of toner-carrier and toner-toner charge-admixexchange processes. The model starts with the “perfect” charge admix case, and this is then used as a base for the development of a model for atypical charge admix processes. The model also describes toner charging performance from the initial developer charge-up step through the charge spectra of the final toner admix step. In this paper, predictions from the conceptual model are also reviewed for various levels of developer mixing and aging.