OBPS recently added the first of a two-phase project devoted to the opera and ballet scores of the Russian State Library (RUS-Mrg). The first phase consists primarily of non-Russian composers with the upcoming second phase highlighting works by Russian composers. The first includes many French, Italian, and German works in translation from Russian publishing houses, both domestic and foreign. Notable Russian publishers include A. Gutheil and P. Jurgenson in Moscow and M.P. Belaieff in Leipzig. Predictably, this first upload includes works by many Italian, French, and Austro-Germanic composers (Donizetti, Gounod, Mozart etc.) who are well represented in the OBPS database. Works in Polish by composers Stanisław Moniuszko, Karol Szymanowski, and Władysław Żeleński bring a more specialized diversity to the database. These nationalist composers exemplify Polish opera composition in the middle to late Romantic period. Scores of fifteen ballets have also been added to the database including works by Beethoven, Delibes, and Pugni, among others.