Ward, thanks for explanations and references. I have one more question. XMLRPC is similar to SOAP in abilities and applications, as I understand. But on my personal opinion, if to compare, XMLRPC has much more winning data representation. "Envelope" is terrible itself. Here question, whether is necessary to have two realizations of the RPC using XML? I think that it is not profits integration and compatibility. It seems to me that it is necessary to seek cooperation between developers for establishing of the trade-off decision. -- Best regards, Timur mailto:Timur@niist.ntu-kpi.kiev.ua