The valence theory has been one of the leading tendencies in modern linguistics for a while. It appeared with reference to the study of the semantico-syntactic and functional activity of words in speech. Traditionally, the term valence refers to the ability of the verb (or other parts of speech) to create around it open positions, the so-called voids (empty spaces), filled with mandatory and / or optional actants and sirconstants. There are various classifications of valences, so the present article aims at presenting a review of the existing theories in this area. Several types of valencies have been identified and described.