I trying to use and / with element values but I just can't get it to work. If I do it with attrubute values it works like a charm. Test.xml <test:config xmlns:test="http://www.example.org/Test" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.example.org/Test Test.xsd "> <test:location id="id1" path="/path2"> <test:roles> <test:role>role1</test:role> <test:role>role2</test:role> <test:role>role2</test:role> <!-- DUPLICATE: FAIL VALIDATION --> </test:roles> <test:action name="action1"> <test:roles> <test:role>role1</test:role> <test:role>role1</test:role> <!-- DUPLICATE: FAIL VALIDATION --> <test:role>role3</test:role> <!-- NOT DEFINED: FAIL VALIDATION --> </test:roles> </test:action> </test:location> </test:config> I want ensure that roles are only defined once and that the roles defined under the action element are only those defined at the upper level. Test.xsd <xs:element name="config"> <xs:complexType> <xs:sequence> <xs:element ref="test:location" maxOccurs="unbounded" /> </xs:sequence> </xs:complexType> </xs:element> <xs:element name="location" type="test:LocationType"> <xs:key name="keyRole"> <xs:selector xpath="test:roles" /> <xs:field xpath="test:role" /> </xs:key> <xs:keyref name="keyrefRole" refer="test:keyRole"> <xs:selector xpath="test:action/test:roles" /> <xs:field xpath="test:role" /> </xs:keyref> </xs:element> <xs:complexType name="LocationType"> <xs:sequence> <xs:element ref="test:roles" minOccurs="0" /> <xs:element name="action" type="test:ActionType" minOccurs="0" maxOccurs="unbounded"/> </xs:sequence> <xs:attribute name="id" type="xs:string" use="required"/> <xs:attribute name="path" type="xs:string" use="required"/> </xs:complexType> <xs:element name="roles" type="test:RolesType"> <xs:unique name="uniqueRole"> <xs:selector xpath="." /> <xs:field xpath="test:role" /> </xs:unique> </xs:element> <xs:complexType name="RolesType"> <xs:sequence> <xs:element name="role" type="xs:string" maxOccurs="unbounded"/> </xs:sequence> </xs:complexType> <xs:complexType name="ActionType"> <xs:sequence> <xs:element ref="test:roles" /> </xs:sequence> <xs:attribute name="name" type="xs:string" use="required" /> </xs:complexType> The validation fails with these messages: Description Resource Path Location Type cvc-identity-constraint.3: Field "./test:role" of identity constraint "keyrefRole" matches more than one value within the scope of its selector; fields must match unique values. Test.xml /filebrowser-ejb/src/test/resources line 15 XML Problem cvc-identity-constraint.3: Field "./test:role" of identity constraint "keyrefRole" matches more than one value within the scope of its selector; fields must match unique values. Test.xml /filebrowser-ejb/src/test/resources line 16 XML Problem cvc-identity-constraint.3: Field "./test:role" of identity constraint "keyRole" matches more than one value within the scope of its selector; fields must match unique values. Test.xml /filebrowser-ejb/src/test/resources line 9 XML Problem cvc-identity-constraint.3: Field "./test:role" of identity constraint "keyRole" matches more than one value within the scope of its selector; fields must match unique values. Test.xml /filebrowser-ejb/src/test/resources line 10 XML Problem cvc-identity-constraint.3: Field "./test:role" of identity constraint "uniqueRole" matches more than one value within the scope of its selector; fields must match unique values. Test.xml /filebrowser-ejb/src/test/resources line 9 XML Problem cvc-identity-constraint.3: Field "./test:role" of identity constraint "uniqueRole" matches more than one value within the scope of its selector; fields must match unique values. Test.xml /filebrowser-ejb/src/test/resources line 10 XML Problem cvc-identity-constraint.3: Field "./test:role" of identity constraint "uniqueRole" matches more than one value within the scope of its selector; fields must match unique values. Test.xml /filebrowser-ejb/src/test/resources line 15 XML Problem cvc-identity-constraint.3: Field "./test:role" of identity constraint "uniqueRole" matches more than one value within the scope of its selector; fields must match unique values. Test.xml /filebrowser-ejb/src/test/resources line 16 XML Problem cvc-identity-constraint.4.1: Duplicate unique value [role1] declared for identity constraint "uniqueRole" of element "roles". Test.xml /filebrowser-ejb/src/test/resources line 9 XML Problem cvc-identity-constraint.4.1: Duplicate unique value [role1] declared for identity constraint "uniqueRole" of element "roles". Test.xml /filebrowser-ejb/src/test/resources line 15 XML Problem cvc-identity-constraint.4.2.2: Duplicate key value [role1] declared for identity constraint "keyRole" of element "location". Test.xml /filebrowser-ejb/src/test/resources line 9 XML Problem cvc-identity-constraint.4.3: Key 'keyrefRole' with value 'role3' not found for identity constraint of element 'location'. Test.xml /filebrowser-ejb/src/test/resources line 19 XML Problem If I comment out the lines that should fail, validation still fails now with these messages: Description Resource Path Location Type cvc-identity-constraint.3: Field "./test:role" of identity constraint "keyRole" matches more than one value within the scope of its selector; fields must match unique values. Test.xml /filebrowser-ejb/src/test/resources line 10 XML Problem cvc-identity-constraint.3: Field "./test:role" of identity constraint "uniqueRole" matches more than one value within the scope of its selector; fields must match unique values. Test.xml /filebrowser-ejb/src/test/resources line 10 XML Problem What am I doing wrong?