The desire for preserving a portion of this country's cultural resources has forced archaeologists and resource managers to make determinations about the relative significance of archaeological sites. Decisions are made regarding which sites are to be preserved and which must be dismissed in the name of progress. The first half of this thesis traces both the history and evolution of the significance concept, and briefly reviews some of the means and strategies archaeologists use in making significance evaluations in the face of continued economic development and a rapidly changing theoretic and methodological discipline. The second half of this thesis demonstrates a proposed significance preservation model for the known archaeological resources using data from the Upper Yalobusha River Basin in north central Mississippi. Unlike preservation strategies that evaluate resource significance on a site-by-site basis, this model establishes preservation areas based on a twenty percent representative sample of the known cultural resources in the region.