The evaluation of the significance of archaeological resources, mandated by federal, state, and local statutes, has forced American archaeologists to justify why sites or their contents should be preserved. The currently popular approach toward evaluation emphasizes determination of the relevance of archaeological resources to regional research problems. However, this approach fails to recognize that resources have values to research problems not yet conceived. It is argued, therefore, that evaluation must focus directly on the observational properties of resources. Using Spaulding's article, "Dimensions of Archaeology," as an initial inspiration, five such properties were defined: variety, quantity, clarity, integrity, and environmental context. A recent project in coastal California provides examples of how this alternative approach may be used.