It was generally assumed that with Prince Igor, Rimsky-Korsakov edited and orchestrated the existing fragments of the opera while Glazunov composed and added missing parts, including most of the third act and the overture.
En xeral, asumíase que con Knyaz Igor, Rimskii-Korsakov corrixira e orquestrara os fragmentos existentes da ópera mentres Glazunov compuña e engadía as partes faltantes, incluíndo a maior parte do terceiro acto e a abertura.