Structural Metadata & Standardization Failures: Just a Little Bit of History Repeating

The design of the Extensible Markup Language has placed a premium on modularity and promoting the re-use and inter-mixture of pre-existing tag sets in the service of new goals. While this design tends to promote standardization, it clearly does not guarantee it, as the multiplicity of competing XML languages for rights expression or word processing demonstrates. This paper examines the history and evolution of structural metadata standards within the digital library community to help identify factors leading to production of multiple markup languages competing for similar or identical ecological niches.