This article investigates as-clauses in Catalan and other Romance languages. It observes that as-clauses can display an overt or canonical realization of the verbal complement or a gap. It argues that, when as-clauses display an overt verbal complement, they are interpreted as manner adjuncts, and when they display a gap in the verbal complement position, they are interpreted as evidential adjuncts. Whereas manner as-clauses in Catalan are analyzed as adverbial relative clauses, it is claimed that evidential as-clauses involve an operator (tal) moving to an A’-position; such an operator abstracts over a propositional variable in the verbal complement position and is coindexed with the matrix clause. This analysis permits to grasp the very deep differences presented by two superficially very similar constructions and to provide a rather simple account of several idiosyncrasies of evidential as-clauses.