Trough this final paper we have explained in detail the procedure of conclusion the administrative contract and we are tried to demonstrate the importance of introducing an administrative contract into administrative law. Each contract is defined as the consent of the manifestation of the will of two or more entities for the achievement of permitted legal effects. The administrative contract was introduced into the Law on General Administrative Procedure under which the conditions governing contracts differ from others. The characteristics of the administrative contracts are that as one of the subjects there is always a public legal person who wants to achieve a certain public interest, which acts as the holder of the public authority and adheres special powers, and the conditions of they are foreseen in special regulations. When determining the name of the administrative contract prescribed by the General Tax Law, the other names have been proposed, but since the Institute of Administrative contract has already been introduced to the General Administrative Procedure, the name has been retained. The administrative contract as prescribed by the General Tax Law represents an administrative legal relationship between the public administration and a private person based on the will of the two sides. The active inclusion of citizens in two-way communication with public administration and the giving opportunities for participation in administrative affairs is an important step towards the realization of the modernization of public administration.