I found an article comparing WS-RF and WS-Context. http://www3.sys-con.com/webservices/rotate2.cfm This is relevant to our Asynchronous Activities profile. Guy Rixon gtr at ast.cam.ac.uk Institute of Astronomy Tel: +44-1223-337542 Madingley Road, Cambridge, UK, CB3 0HA Fax: +44-1223-337523