ENThe article analyses the cooperation between the burghers and nobility of the Kowno (Kaunas) urban district during the implementation of the Law on Towns issued by the Sejm of the Polish- -Lithuanian Commonwealth on 18 November 1791, as well as the Constitution of 3 May 1791. Different forms of cooperation were identified: members of nobility joined the burghers by accepting the city law; helped to implement the urban laws issued by the Sejm; participated in the organization of the meeting of Kowno district representatives; assisted in finding the privileges of towns and small towns; were active in the governance institutions of the town and urban district; represented Kowno and its district in the Sejm and other institutions of the country. Although the listed activities were a step to overcoming estate barriers, they were disrupted by the collapse of the Four-Year Sejm. [From the publication]