Pronominal clitics comprise one of the important traits of the majority of West Iranian languages. Nevertheless, while these person clitics have been the subject of virtually systematic studies in certain languages, e.g. Central Kurdish dialects, and Persian, they are hardly studied in the majority of languages where they are attested. More specifically, the existing scholarship has faintly dealt with the rise of procliticization, the development of person marking system, the placement of clitics, the cluster internal ordering of clitics, and the clitic-affix combinations. This study is an attempt to fill the lack of knowledge across the aspects mentioned. The development of proclitic attachment forms an integral part of the thesis.