This dissertation examines the pronominal clitics of Tocharian A and B and develops a modelthat best accounts for their distribution. After reviewing the phonological, morphological, and syntactic characteristics and chief uses of the Tocharian pronominal clitics, a morphosyntactic model is developed, which accounts for the attested uses and predicts gaps in their distribution. It predicts that the Tocharian pronominal clitics cannot represent the possessor associated with a transitive subject or the complement of the adposition contained in another nominal expression. The model also suggests that when a pronominal clitic represents the possessor associated with the subject of an intransitive verb, the verb belongs to the so-called unaccusative verbs. Furthermore, it accounts for the restricted distribution of PCs in the sentences where multiple arguments are pronominal. When the indirect and direct objects of a ditransitive predicate are pronominal, pronominal clitics consistently represent the indirect object. The morphosyntactic analysis advanced in this dissertation derives this distribution since a licensor, which looks for a pronominal argument, finds the indirect object before the direct object. Tocharian pronominal clitics sometimes co-occur with the overt nominal expression it corefers with. In such cases, the doubling pronominal clitic indicates the doubled associate to be topical.