Book excerpt: This book discusses a class of Reduced Constructions which exhibit both mono- and bi-clausal characteristics. In Spanish, as well as other Romance languages, the most salient mono-clausal characteristic is the possibility of clitic climbing, i.e. the possibility of an object clitic attaching to a verb that is higher (in the appropriate sense) than the verb which selects the object to which the clitic corresponds. Reduced constructions come in essentially two varieties: clause reduction (or restructuring) constructions and union (or causative / perception verb)constructions. There has been a good deal of work on a number of aspects of reduced constructions; here the author discusses work in three areas: the analysis of pronominal clitics, the structure of clause reduction and union constructions (and how these treatments interact with the analysis of clitics to yield an account of clitic climbing), and the encoding of embedded subjects in union constructions.