His third concern was to maintain hegemony within the Ayyubid domains without resort to force. He proved to be a skilled diplomat in this respect and managed to avoid any confrontations after 1201. Of particular importance was the marriage of his daughter Dayfa Khatun to Saladin's son Az-Zahir Ghazi of Aleppo in 1212, which marked the end of the rivalry between the two branches of the family. Al-Adil also undertook a major programme of refortification throughout his domains, and the massive citadel of Damascus was one of his most notable achievements in this respect.