Is it possible to place clientaccesspolicy.xml file into site root for the SharePoint Online, which is part of Office 365 subscription? The point is to use Silverlight CSOM from a Silverlight Application running in another environment (on-premise, or hosted). I couldn't find any solution for the clientaccesspolicy.xml. There are only work-arounds suggesting to combine the external (to the Office 365) Silverlight Application with a web/wcf/ria services, that would use the .net client object model to query the data.