One of the basic constitutional principles is the principle of two-stage proceedings. Raising it to a constitutional rank demonstrates its importance. The adopted model of two-stage administrative proceedings intends to guarantee that the decision issued by the administrative authority will be consistent with the law. The means of such verification constitutes an appeal. The article aims to present the most important institutions related to the principle of two instances and analyze them. It is undoubtedly an appeal, but also a waiver of the right to appeal, an objection and a cassation decision (Article 138 § 2 of the Polish Code of Administrative Procedure), which is the most controversial. For this purpose, the author uses dogmatic and legal methods.
