1. A method comprising: generating a unified model data index by indexing a plurality of shared syntax elements describing at least one of a plurality of objects, attributes, and relationships of a plurality of data artifacts, each of said plurality of data artifacts corresponding to one of a plurality of engineering and non-engineering domains including hardware, software, electrical engineering, mechanical engineering, system architecture, manufacturing, computer-human interaction, and industrial design; creating instances of an engineering reference model describing model properties including system, sub-system, product line, component, and part that define blocks and relationships between each of said data artifacts for each of said plurality of engineering and non-engineering domains; and enriching said unified model data index by adding said relationships having a plurality of shared syntax elements of at least one instance of said engineering reference model to said plurality of shared syntax elements of said unified model data index to provide an enriched unified model data index.