ObjectivesThis article aims at characterising the current Fundamental Law ("constitution") of the Vatican City State with particular attention given to the amendments introduced by Pope Francis in 2023. The article will attempt to answer the following questions: What was the reason for the reform of the Vatican City State? What is the structure of the Vatican City State? What distinguishes the Vatican City State from other states?Material and methodsThe article will use the sources of law and available literature on the subject. Historical-legal and dogmatic-legal methods will be used.ResultsIn the article the reasons for the reform were presented. For this purpose, the origins, the concept and the specificity of the Vatican City State as guarantor of the independence and sovereignty of the Holy See were described. This was followed by a characterisation of the governing system of the Vatican City State. This issue required an in-depth analysis due to the fact that the Vatican City State, despite being an absolute monarchy in which the Sovereign enjoys full power, has specialised bodies equipped with legislative, executive and judicial functions, which they always exercise on behalf of the Pope.ConclusionsPope Francis justified the necessity of the reform by “the needs of our time”. In this context, he recalled that the Vatican State was created in 1929 as an instrument to ensure the Holy See’s independence and guarantee its sovereignty also in the international arena. It must be pointed that the structure of the Pontifical Commission for the Vatican City State has been changed, which can also include “other members”, thus also lay persons.