If I have nested union types (unions of unions) then does unionMemberSchema give the "innermost" schema component, or the "outermost"? This feature was added to DFDL to support PSVI infosets. My use case is not that, but in implementing this feature I want to make sure I am doing it consistently with what is needed for the original PSVI need. Specifically, if I have a valid Element Infoset Item for element 'u' below, does unionMemberSchema give a SCID for an outerUnion or innerUnion schema component? <element name="u"> <simpleType> <union memberTypes="outerUnion1 outerUnion2"/> </simpleType> </element> <simpleType name="outerUnion1"> <union memberTypes="innerUnion1 innerUnion2/> </simpleType> <simpleType name="outerUnion2"> <union memberTypes="innerUnion3 innerUnion4/> </simpleType> <simpleType name="innerUnion1"> <restriction base="xs:int"> ... </restriction> </simpleType> <simpleType name="innerUnion2"> <restriction base="xs:int"> ... </restriction> </simpleType> <simpleType name="innerUnion3"> <restriction base="xs:int"> ... </restriction> </simpleType> <simpleType name="innerUnion4"> <restriction base="xs:int"> ... </restriction> </simpleType> Mike Beckerle | OGF DFDL Workgroup Co-Chair | Tresys Technology | www.tresys.com Please note: Contributions to the DFDL Workgroup's email discussions are subject to the OGF Intellectual Property Policy <http://www.ogf.org/About/abt_policies.php>