The presentation’s main point is: all good pieces of analysis are preliminary to the recognition of a grammar. The first part (“Analysis in the forest of musical studies”) – pinpoints the location of analytical studies in the broader field of various musical disciplines. Part 2 deals with the different meanings of the concept ‘musical rule’, and reaches the following statement: every kind of music – more or less provided with explicit compositional directions – is based on a system of rules which belongs to a grammar, common to different pieces by different composers acting in the same epoch and genre. That is: every piece of music belongs to a grammar of a particular style, because even in the most revolutionary piece of art, rules do exist. In part 3 the concept of ‘grammar’ is discussed. This concept is strictly related to the concept of rule because rules are  the material of the grammar. The two concepts are not equivalent, however: single rules have to be ordered and systematized in order to become part of a grammar. Moreover, the nature of the rules emerging from analysis (and the grammar to which they belong) must not be confused with the kind of procedures which act when the rules are concretely applied. In fact, a rule describes the functioning of a single phenomenon (that is the facet of ‘knowledge’), but also sets limits on the use of the phenomenon itself (the ‘operative’ facet). The central idea of grammar finds its realisation in a conceptual tool able to ‘describe’ and to ‘utilise’ the rules governing the coherent connections among all the elements constituting a musical unit of a higher level. So, we can say that a grammar is in itself an ordered system of rules. A grammar as a cognitive tool is an explicit and conceptual description of grammatical competence.