Specifies the XML Schema syntax, mechanisms and conventions that: - provide an open, vendor-neutral framework for the description of geospatial application schemas for the transport and storage of geographic information in XML; - allow profiles that support proper subsets of GML framework descriptive capabilities; - support the description of geospatial application schemas for specialized domains and information communities; - enable the creation and maintenance of linked geographic application schemas and datasets; - support the storage and transport of application schemas and datasets; - increase the ability of organizations to share geographic application schemas and the information they describe.