The Russian artist El Lissitzky's attempt to explain the new Soviet revolutionary architecture and its ideological, socialist theory. This meant, among other things, how it was possible to deal with social concerns such as living in good housing and the questions of individualism and a collective life.
The interesting thing about the book is the theoretical link between ideas in Western and Central Europe and those in Eastern Europe and their interactions. El Lissitzky spent a lot of time in Germany, working closely with Mies van der Rohe and Theo van Doesburg. He influenced architects and artists throughout Europe.
His main ideas about the new architecture can be found here.