A Solr schema is needed that acts a common model for Sidora content. It should be optimized for interoperability and therefore cannot support queries too specialized for specific metadata or data formats. However, it should accommodate marshalling results of queries from more specialized Solr schemas or the results from other indicies in the futures. It must support facted search, those facets being selected to support both general search and search over Sidora specific capabilities needed for its discovery features.