We have chosen to implement the interface UP! CRM on a framework which would enable to standardize the organization of the information through an architecture/configuration that is based entirely on the web. UP! CRM provides two client bridge mode. The first (UP! CRM IE) based on HTML, ASP and ActiveX controls. The second (UP!. NET) developed entirely in c# with. framework.NET. The forms in both modes are described by XML. The XML files that describe the forms of UP! CRM control its visual appearance, functioning, the events and some interactive properties. All this to make room for those who customize the system, to define new aspects of the interface, to insert new events and controls and manage new properties which are undefined in the drafting/drawing up of the project.