Benkankyoku was an important office that was in charge of practical business of Daijokan under the Giseikan (Daijin, Dainagon, Chunagon, Sangi), and was collectively called Daijokan Sankyoku together with Shonagon.
議政官（大臣(日本)・大納言・中納言・参議）の下で太政官の実務を担う枢要の部署であり、少納言と合わせて太政官三局という。