A system for validating a document against an encompassing schema and at least one referenced chameleon schema, comprising: a working schema register for storing a working schema using the encompassing schema as a starting point; chameleon schema identifier for identifying a chameleon schema encompassed by the encompassing schema; an existing indexed schema engine for incorporating an existing indexed schema into the working indexed schema if there is an existing indexed schema associated with the encompassing schema and the chameleon schema; a new indexed schema engine for creating a new indexing schema based on the chameleon schema and the encompassing schema namespace and incorporating said new indexed schema into the working schema if there is no existing indexed schema associated with the encompassing schema and chameleon schema; and a schema validator for validating the document using the working schema.