Dictionaries of linguistic doubts belong to a type of lexicographic genre whose boundaries are not crystal-clear, even though these may seem to be perfectly defined. They are often confused with other repertoires, and represent a fairly wide range of dictionaries, at least in what concerns their microstructure. As for the sources they draw from, they follow in most cases the norm established by the Real Academia Española. In this chapter, I will describe some of the most well-known ones in order to evaluate them, and make proposals that may contribute to improve future products, by suggesting criteria that take into account the needs and skills of potential users.