On a festive day for all museum workers — May 18 — the Polotsk Museum of Local History is crowded. On the International Museum Day, 11 Nizhne-Pokrovskaya Street, the exhibition "ProSOVTORG, or the development of trade in Polotsk in 1919-1991" was visited by members of the club "Multicolored World", which was established back in 2017 at the F. Skaryny Central District Library. Residents of Polotsk, for whom many things at the exhibition were familiar, listened with interest to the guide's story about who and what traded in Polotsk 40, 60 and even 90 years ago. A real gift for museum workers was the acquaintance with the wife of the grandson of A.A. Dobrovolsky, an honorary citizen of the city of Polotsk, who stood at the origins of the development of consumer cooperation on the canvas in the 1920s. Some visitors shared with the researchers their vivid impressions of the city's trade, and most of them left the museum with a sense of nostalgia for the soviet past.