Hello Eduardo, I guess, amount is a Basic Core Component (BCC) for example. We have to define all the BCCs according the ebXML Core Component Specification V1.85 And this specification says on page 11 that a Basic Core Component represents a singular business concept with a unique business semantic definition. A Basic Core Component will be constructed by using a Core Component Type (CCT). And a CCT consists of one and only one Content Component and one or more Supplementary Component which giving an essential extra definition to the content component. The Content Component derives from a primitive type and will be used to express the content of a CCT only. The Content Component itself have no addtional meaning, like price. Therefore, your definition will be not agree with the ebXML Core Component Specification. If you would like to use a child-element for expressing the content it self, we have to define it as following: <amount currency= Y > <content>X</content> </amount> or <amount> <content currency= Y >X</content> </amount> The ebXML CCS says that the Content Component will be derived from a primitive type. And a primitive type is according the XML Schema Definition a simple type definition. Therefore, it is not necessary to express the content itself within an addtional child element. The following example will be enough: <amount currency= Y >X</amount> And we have to define that all another possibilties for defining a Core Component Type are prohibited. Regards, Gunther