Kenneth B. Sall is an XML consultant. He has sixteen years' experience in information technology, including eight years of Web development. Sall was a key contributor to the Astronomical Instrument Markup Language for NASA/Goddard Space Flight Center. In addition, he maintains the XML section of Web Developers Virtual Library (WDVL.Internet.com) and has written many articles and spoken extensively on XML. Sall offers XML training courses targeted for different audiences.