Convention 15 of the Shadow Proclamation
The Convention 15 of the Shadow Proclamation was a subsection of the Shadow Proclamation. It dealt with the cessation of hostile actions in order to parlez. (TDA: Peacemaker)
The Doctor used it to seek audience with the Nestene Consciousness. (DW: Rose)
Rose Tyler tried to invoke Article 15 among other aliens, places, and things she encountered in her travels with The Doctor to try to convince the Sycorax to leave Earth alone, though they merely laugh at her. (DW: The Christmas Invasion)
The Doctor yet again used this phrase against the Isolus, but it did not care. (DW: Fear Her) but he used it successfully to communicate with the Clade. (TDA: Peacemaker)