Saxon implements the xsl:import-schema declaration in the enterprise edition product Saxon-EE only.

The namespace attribute specifies the target namespace of the schema to be imported. The attribute should be omitted when importing a schema with no target namespace.

The schema-location attribute specifies where the schema document can be found. This URI is passed through the URIResolver in the same way as the URIs used on xsl:include and xsl:import. The attribute can be omitted only if a schema for the required namespace has already been loaded in the Configuration, for example if it has already been imported from another stylesheet module.

For further information see Schema Processing.