Hi, Firefox doesn't come preinstalled with Parental Controls but you can go about two ways of doing this. *Installing an add-on to block sites you want [[https://addons.mozilla.org/en-US/firefox/addon/blocksite/]] Note that this only works for Firefox and people can still access the sites on a different browser. *Installing a content blocker for your entire computer. This works on all browsers as opposed to the add-on above. My sister uses this and it's really amazing. The software is very difficult to disable or remove without an administrator password. The uninstaller requires the administrator password to run, and if the service or process is stopped all web access is disabled. Similarly, attempts to modify the program from the windows registry or file system will also lead to all web access being disabled. You can download it at http://www1.k9webprotection.com/