Lembede became part of the National Provisional Committee, which was formed in 1944 to oversee the process of the formation of the ANC Youth League. On 10 September 1944 the Youth League was officially formed and Lembede took over from William Nkomo as the Youth League general president. Nkomo served as the Provisional Chairperson since the beginning of 1944. Lembede contributed immensely in the drafting of the ANC Youth League Manifesto. Lembede also served in various ANC positions. In 1944 he was elected ANC Provincial Assistant Secretary in the Transvaal. Two years later Lembede was seconded to the ANC National Executive Committee and National Working Committee under the leadership of Dr Xuma .