This thesis presents a study of microvariation in (long-distance) restrictive relative clauses and related constructions in Dutch. It shows that a proper understanding of the attested microvariation, and in particular pronoun doubling in long-distance relative clauses and (embedded) wh-questions, yields new insights into the structure of A-bar chains, the syntax of relative clauses, the structure of the left periphery and the nature of (relative) pronouns and their relation with complementizers. More specifically, this thesis provides a unified analysis of doubling in relative clauses and (embedded) wh-questions, a reevaluation and reinstatement of (a revised version of) the traditional head external analysis of relative clauses, and a new implementation of an underspecification approach to so-called multipurpose pronouns and complementizers. This study is of relevance to scholars working on morphosyntactic microvariation, doubling phenomena, the structure of long-distance A-bar chains, the syntax of relative clauses and the nature of relative pronouns and complementizers, as well as to a general syntactic readership