With this chapter, dedicated to the syntactic dictionaries, we try, first of all, to analyze the peculiarities, achievements and disadvantages of the Diccionario de construcción y régimen de la lengua castellana, of R. J. Cuervo, unique dictionary in its modality. After analyzing the characteristics that we have considered essential in the same, we have tracked other proposals of syntactic dictionary, among which the Diccionario de construcciones sintácticas del español. Preposiciones, by E. Náñez Fernández, although very particular in terms of the dictionary concept itself. For this reason, we also refer to the proposals of bilingual dictionaries of valences as possible referents for the development of an exclusive valence dictionary for Spanish.