The Xiāng dialects comprise one of the major families of modern Sinitic languages. However, a number of modern linguists doubt that, as currently constituted, this group forms a valid taxonomic unit. In confronting this problem, the present work identifies twelve dialects, currently considered to be Xiāng, which can be associated with one another on the basis of a complex of shared innovations, vis-à-vis earlier common Chinese sound systems. This group of dialects, which clusters in the middle portion of the Xiāng-speaking area, is designated here as "Central Xiāng"; and its members are subjected to a comparative reconstructive analysis, resulting in a phonological proto-system, called "Common Central Xiāng". The book also examines related questions of demographic and migration history, together with possible historical connections between Central Xiāng and the Gàn family of dialects. It is suggested that Gàn and Central Xiāng may ultimately have belonged to a dialect continuum and that this possibility should be investigated in future studies.