The author of the book - candidate of architecture, famous St. Petersburg local historian I.I. Lisaevich - talks about the birth of buildings intended for trade and financial institutions. These are washing and living rooms, exchange, customs, banks, banking and trading houses, mutual credit societies, joint-stock companies. Buildings for these institutions in St. Petersburg were erected by leading architects. Especially a lot of them were built on Nevsky Prospekt and adjacent streets. They are today the decoration of our city. Many of them return to the original function.