The demarcation of the content and the purpose of the concept of public administration has not only theoretical importance but also a practical one regarding the field of the right of a person aggrieved by a public authority, on the one hand, and administrative litigation area, on the other side. As the science of law can not ignore the positive law, it is understood that the demarcation of content and purpose of the concept of government requires an operation to explain the legal regulations in force in relation to what we might call the doctrine’s constants in a democratic system. The inter-war doctrine in our country, in line with the principle of separation of powers, granted, constantly, that the administrative law comprises the rules by which the activity of the executive power is exercised ,but also contains extensive discussion about the limits of that power to the legislative power, of that power to court. Hence the variety of theoretical solutions on the content and purpose of the concept of state administration, or simply of administration. It’s the period of crystallization of the classical doctrine in Europe, in general, which is marked by strong opinion fights, majoring those from the French school, theoretical disputes, which influenced the Romanian doctrine. Regarding the post-war Western doctrine, we can retain the optical changes, especially in France after 1958, regarding the land concept of separation of powers, were reflected in their understanding of public administration. The removal from the classical paradigms challenged not only the relationship between the executive and the legislative, and, in this context, the relationship executive - administration, but also fundamental reference elements of the classical school, namely, the public service and the public interest.