The research dealt with the efforts of the distinguished scholars, critics, and critics in the Basra school in the second and third centuries AH, and these efforts are represented by the efforts they made, in collecting, compiling, and classifying various hadith works, and the journeys they took to other hadith schools, in which they benefited, and benefited from, in increasing Collecting the Prophetic hadith, disseminating it, seeking high mastery, learning about the conditions of the narrators in it, and explaining the reasons for the hadiths in the hadith narrations, all of that and more, helped in preserving the Sunnah of the Prophet, may God bless him and grant him peace. When he touched on it, substitution, change, and distortion, they explained that from Through an integrated curriculum, drawn up by its scholars, the eminent critical imams of the time, who were able to explain these defects, along with the rest of the eminent critical imams in the other hadith schools.