systemic forms of preferential marriage may have wider social implications in terms of economic and political organization. in a wide array of lineage-based societies with a classificatory kinship system, potential spouses are sought from a specific class of relative as determined by a prescriptive marriage rule. insofar as regular marriages following prescriptive rules occur, lineages are linked together in fixed relationships; these ties between lineages may form political alliances in kinship dominated societies. french structural anthropologist claude lévi-strauss developed alliance theory to account for the "elementary" kinship structures created by the limited number of prescriptive marriage rules possible.