Marriage. The major consideration in a marriage was ownership of sacred bundles. A household with an important clan bundle usually selected a son-in-law from the same clan as the daughter's father. A family with an important bundle might arrange a marriage by presenting a sacred white buffalo cow robe to the prospective son-in-law, thereby committing him to sponsoring sacred ceremonies that eventually finalized the marriage. Families with less important bundles simply Exchanged gifts, or, more simply, the young woman moved in with her husband. The ideal marriage was matrilocal, where the young man moved in with the young woman's family, but residence was quite flexible and depended on the type of Marriage ceremony, the amount of space available in a lodge, and relationships within the family. A man could have more than one wife and, in the ceremonial form of marriage, the bride's sisters were contracted to the groom, but most men found one wife sufficient.
Domestic Unit. Until the dispersal to the farmsteads, the basic unit was the lodge group composed of several families of related women who occupied the same earthlodge. Following the dispersal, related families settled near each other, and the extended family continues to be an important factor in Mandan life.
Inheritance. Traditionally, the most important property belonged to the lodge group or the clan and inheritance passed from mother to daughter or father to son. The allotment act contained provisions for inheritance of allotted land and, unless the owner leaves a will, property is now divided equally among the heirs.
Socialization. Children were praised and encouraged and never punished by their parents. When discipline was necessary, the mother's brother or another clan member living outside the lodge was asked. Today Mandan children attend school on or off the reservation and some continue through college.