"Shadd" is a symbolic belt which was being tied around the waist of the neophytes and novices of fityan, aṣnaf and some sufi communities in an initiation ceremony where the earlier waist-tied (mashdud) members presented. By this ceremony, the person became, provisionally or permanently, a member of the aforementioned communities. It has been emerged at least in the 7th century and continued in some Sufi orders so far. In addition to be a sign of acceptance in the mentioned groups, shadd has also functioned in some other ways; among the traders, it has somehow been as a license for their job and among some Sufis functioned as lubs i khirqa ceremony. In this paper, the function, history, material, apparent features, conditions and terms of mashduds ceremony details have been investigated. The study is based on the futuwwat-namas and kasb-namas, particularly the Persian ones which have been seldom studied in previous surveys.