One household head is selected by the cluster members to act as the tumpuk spokesman. A parish consists of local groups whose members are affiliated with a single mosque. Sometimes, clusters and parishes are one and the same. Among the Northern Sinama, both men and women share in agricultural labor and engage in trade. Fishing, building boats, and working with iron are primarily male occupations.
Women generally weave mats and market pottery.
All Northern Sinama are Shafiite Sunni Muslims . The paki preside over all major rites, act as religious counselors, and conduct minor rites of thanksgiving. Friday prayers are performed in the parish mosque and are the climax of a weekly cycle of daily prayers. Spirits of the dead are thought to remain in the vicinity of their graves. These spirits require offerings for appeasement.