I have developed a web server based on twisted-web that acts as a gateway between the SRU search protocol and the Z39.50 search protocol. ( Details at http://www.loc.gov/z3950/agency/ ) Each SRU search request opens a thread which performs a Z39.50 search on a remote target and then returns the results which are converted into the SRU response. Sometimes the connection with the client issuing the SRU request is lost. In a few cases this produces the message "Connection to the other side was lost in a non-clean fashion: Connection lost. ". When several of these non-clean connection losses occur the web server will become unresponsive and will not respond to any new requests. Can anyone help with how I should respond to these non-clean lost connections ?. I can't find any documentation which helps me understand the impact of this type of error. As the connection is lost there is no point in returning any error response, but are there systems resources left allocated which might be causing the server to become unresponsive. Bill -- Bill Oldroyd Technical consultant for The European Library