Today's researchers periodically refer to the extensive scientific heritage of Wassily Leontief, one of the outstanding economists of the 20th century, in order to find solutions to individual problems, both in the global and in the economies of individual countries. The object of consideration of this article is the Leontief differential model. The authors substantiate the need for further development of this model and offer specific forms of its mathematical interpretation. A new reading of Leontief's differential model, the authors believe, will reveal the impact of investment flows from developing countries and emerging markets on various national economies and their groups.