How to restrict a user to viewing only one project?

[Jeff Schaeffer]

I need to be able to restrict a user to viewing only one project out of many, without an ability to create records. How can I do this?

[Nic Brough -Adaptavist-]

You need to work through http://confluence.atlassian.com/display/JIRA/Managing+Project+Permissions

Basically, you need to make your Jira private by default (a new user has no access other than "log in" until they are added to groups and/or roles that they need). Then you can add a permission your user who should only see project X to see it as appropriate.

You will probably not be starting with a "clean" Jira - the default setup, which most admins carry on with until they get the hang of it all, is to have a group of "jira users", which is then used for "allow logging in" AND in the project permission schemes. You'll need to get rid of that, and have a separate group for "can log in" and "general jira user who needs access to projects"