The very flexibility of Dyula kinship makes the choice of a spouse all the more important. Any children born belong, of course, to the husband's kabila, but members of the wife's family are also considered an extremely important category of kin. Formerly, an adolescent or young man whose father was dead could choose to work for his maternal, rather than his paternal, relatives. The choice remains much too crucial an affair to be left to the whims of young men and women. Marriages are arranged by the kin of the bride and groom; most often, neither partner is consulted beforehand. On the groom's side, the decision rests with his father, if he is still alive, or with the senior kinsman under whose authority he is working. On the bride's side, the decision is also in the hands of her father or of a foster parent. Normally, the heads of the descent groups concerned, the kabila tigis – and, in large descent groups, the lu or gba tigis as well – are also consulted, if only as a matter of form.

Islamic law does not exclude the possibility of marriage between close kin. Prohibitions apply, for the most part, to close kinswomen of ascending or descending generations, and to the wives of close kinsmen of ascending or descending generations. On the other hand, within one's own generation, there are relatively few prohibitions, the only ones being sister, ‘milk sister’ and wife's sister.