In this paper, we deal with some changes in valency structure of Czech verbs from a lexicographic point of view. As a first step, two parts of verbal meaning are stipulated: situational and structural meaning.
These two parts of meaning constitute complex meaning structure of verbs. On the basis of three types of asymmetry in the correspondence between components of situational and structural meaning, we distinguish three typologically different changes in valency structure of Czech verbs.
We propose a method of their description in the valency lexicon of Czech verbs, VALLEX. We show that two of them can be described by lexical rules stored in the grammar component of the lexicon whereas the third one can be treated in a special attribute in the data component of the lexicon.