Minutes of the St. Petersburg Committee of the RSDLP (b) - a unique source for studying the events of the 1917 revolution. They reflect the changing mood of the workers of the factories and factories of Petrograd, soldiers of the garrison and sailors of the Baltic Fleet, reveal the view of revolutionary politicians on political and social realities. This collection chronologically continues the publication of the minutes and materials of the PC meetings and covers the period from March to December 1917.