Two namespaces
using System; using System.Linq; using System.Xml.Linq; using System.Collections; using System.Collections.Generic; public class MainClass{ public static void Main(){ XNamespace aw = "http://www.domain.com"; XNamespace fc = "www.anotherDomain.com"; XElement root = new XElement(aw + "Root", new XAttribute("xmlns", "http://www.domain.com"), new XAttribute(XNamespace.Xmlns + "fc", "www.anotherDomain.com"), new XElement(fc + "Child", new XElement(aw + "DifferentChild", "other content") ), new XElement(aw + "Child2", "c2 content"), new XElement(fc + "Child3", "c3 content") ); Console.WriteLine(root); } }