In the paper based on conceptual provisions put forward by Prof. Kozlova, the author sets the objective to identify tendencies that manifest themselves in the development of constitutional and legal institutions at the present stage taking into account the dynamics of the subject of legal regulation, as well as the ongoing transformation of the Russian legal system. In this regard, the author has examined the problem of expanding the field of relations regulated under constitutional law. The author has concluded about the blurring of boundaries between institutions of constitutional law, which entails the problem of attribution of norms to a particular institution. The paper has analyzed the issue of emergence of intersectoral institutions that can be characterized as neither public nor private, as neither substantive nor procedural. This leads to the need to change the very approach to the concept of “institution of law.” It is concluded that constitutional law institutions can contain unwritten legal regulators that can include both rules of natural law and rules of conduct developed directly in the society.