The paper aims at providing an explanation of pronominals in Modern Standard Arabic (hereafter MSA) by assuming that the relation between pronouns and available binders is constrained by the same syntactic condition, i.e., a pronoun cannot be coindexed with a c-commanding NP within its local domain.  It also aims at providing a unified account of two types of pronominals in MSA, referential and bound pronouns. These two types of pronouns have different values for their binders; where a referential pronoun requires a name to be coindexed with; a bound pronoun requires a distinct subject, i.e., a quantifier as its binder. The paper adopts Principle B of the theory of binding to account for these pronouns by examining how this principle can express the content of disjoint reference for pronouns embedded in Ss, NPs and PPs in MSA and  to see whether the phenomenon of disjoint reference in Arabic supports principle (B).