How to keep monitor off when logging in remotely I'm managing an 8-core mac server (fully updated to Mac OSX 10.8.4, all other software is up to date). Multiple users can login remotely to use the machine. Whenever someone logs in remotely, the physical monitor that is connected to the server and sits on my desk turns on, and I can see everything that the user is doing. I can even interfere with their work if I want by moving the physical mouse that is connected to the server, or typing on the physical keyboard that is connected to the server.

Update July 30 2013 If I log in to the local monitor, a remote user can log in and see my screen / hijack my session in the same way that i (locally) can take over their session (remote). Something seems very wrong with that. What settings need to be changed?

How can I stop this behavior? It represents a security risk (other users may not want me viewing their activity, or hijacking their mouse/keyboard), and frankly it's distracting to have someone else's screen/activity going on my desk.

I've messed with a bunch of settings in system preferences, and poked around Ask Different (How to Screen Sharing / VNC to an iMac without waking the display? is close, but still unsolved) for a while, haven't found a solution that works.

Physically turning off the monitor doesn't help, since it 'wakes' up whenever there is activity. Turning the monitor around or unplugging it are also not a solutions I will accept.

Thanks for your help!
Are they logging in as the same user as the currently logged in user?  Post-10.7, Mac OS X VNC supports logging in and either sharing the current desktop, or generating a new virtual desktop.  

HOWEVER, I believe if you're logging in as the same user that's currently logged in, it will take over the computer as though you were accessing it directly.  The solution would then be to create separate users for everyone who accesses the server.

Here's some info about the VNC options.

Hope this helps!