Marriage among the Nuer is brought about by payment of bridewealth and by the performance of certain ceremonial rites. The rites cannot take place without the payments, but transfers of cattle do not by themselves bring about the union. Both are necessary and they proceed in a connected movement towards the full establishment of the union. Each enforces and reinforces the other. The bride's people can, by holding up the rites, put pressure on the bridegroom's people to make the payments due to them, and the bridegroom's people can, by withholding the cattle, induce the girl's family and kin to advance the ceremonies. First one pedal is pressed down and then the other as the marriage is propelled to its appointed end, the birth of children and the sharing of a home. It is undertsood that payments should have reached a certain point before a certain rite is held, and the performance of the rite is a recognition of the transfer of cattle up to that point. Payments of cattle and marriage rites therefore tend to alternate, though there is no fixity about the alternation and no marriage is exactly the same as another in this respect. The new social ties of conjugality and affinity are made stronger by each payment and by each ceremony, so that a marriage which is insecure at the beginning of the negotiations becomes surer with every new payment and rite; both sides, by the giving and receiving of cattle and by joint participation in the rites, becoming more deeply committed to bringing about the union. Therefore a marriage which has reached the final rites may be regarded as a stable union and will generally prove to be so.