When I used to do it : the client install is a custom install with only client libraries (e.g. even exclude the export utility) in a separate OS account that is in neither the oinstall nor the dba groups. Then the client home can be handed over to the apps team. The only issue is that you would be configuring sqlnet tcpip and suffer tcpip stack overheads and not use bequeath and ipc. Hemant K Chitale http://hemantoracledba.blogspot.com sent from my smartphone On Jan 19, 2011 6:27 PM, "Peter Hitchman" <pjhoraclel@xxxxxxxxx> wrote: Hi, Having over the past couple of years started to work with RAC, where the application code runs from another server with an Oracle client install, I am back setting up a single instance where the application code will run on the same machine. It occurred to me that it might make sense to still install an Oracle runtime or instant client for the application to use, as well as the database install, because that way I could upgrade one without interfering with the other. On the down side it means there will be an extra oracle home to maintain and if the releases are different, I might run into issues with the oraenv/dbhome programmes. What do most people out there do, with single instance set-ups? Thanks Pete -- //www.freelists.org/webpage/oracle-l