This paper discusses the syntax of relative clauses in European Portuguese (EP) by focussing on the status of the relativizer que in restrictive and appositive relative clauses. We propose a unified account of que in terms of a D-element and discuss the syntactic implications of this assumption for an adequate analysis of relative clauses in EP. We assume that relative que has properties of demonstrative and interrogative determiners. In restrictive object and subject relative clauses, que occurs as a transitive determiner [ DP que [ NP e]], which selects for a nominal complement, whereas in prepositional and appositive relative clauses, [ DP que] is an intransitive determiner parallel to an e-type pronoun. We discuss the position of restrictive relative clauses in the DP containing the modified noun, and propose that they are merged pre-nominally, in the same fashion as demonstratives.