On the one hand, producers benefit from the big marker, on the other hand, competition between firms is higher on it. In what way does agglomeration of firms affects their effectiveness and the level of competition among them? In Russia elasticity of firm-level productivity to the city size is higher than the one in the developed countries, however, there is no evidence of competitive firm selection. Presenting an article «Agglomeration effects in Russian manufacturing», the professor of RANEPA Tatyana Mikhailova spoke about the result in more detail.