Abstract: A taxonomy of characteristics for products and services is linked via indexing keys to a companion dictionary of terms and to electronic files containing characteristics data on offered products and services. The taxonomy is structured into domains of form, fit, function, and administrative data and permits identification of products and services that can be independent of prior knowledge of the type of product or service or the source of the product or service. In operation, a system user selects required characteristics from the taxonomy and sets values of the fundamental units of measure or identification for each selected characteristic. The system uses the associated indexing keys to locate and display a plurality of available products and services that satisfy those requirements.