Russian Science Citation Index is a bibliographic database of scientific publications in Russian. It accumulates more than 2 million publications of Russian authors, as well as information about citing these publications from more than 2000 Russian journals. The Russian Science Citation Index has been developed since 2009 by the Scientific Electronic Library. The information-analytical system Science Index is a search engine of this database; it offers a wide range of services for authors, research institutions and scientific publishers. It is designed not only for operational search for relevant bibliographic information, but is also as a powerful tool to assess the impact and effectiveness of research organizations, scientists, and the level of scientific journals, etc.