Of all the procedures regulated by legal acts recognized as full constitutions, the provisions regulating the changes to the constitution play a particular role in the system. Their design determines the possibility or impossibility of adapting the basic law to the changing social, economic and political realities, which may reflect the constitutional stability, but it also stabilizes the constitution of a state into a certain shape. The proposed divisions, as well as the precise instruments of constitutional classification based thereon, can facilitate academic discourse and enrich didactics. The subject of the article is an analysis of the Greek constitution in the context of a system of classification, which differentiate this type of legislation into rigid and flexible.