BrijnSMS is a small script written to allow authenticating and logging of messages send thru SMS Client. SMS Client is a UNIX command line based utility which allows you to send SMS messages to mobile phones and pagers. BrijnSMS is written in PHP and uses Mysql as database back-end. The BrijnSMS administrator can create user accounts for people that are allowed to send messages. He can also add people that can receive SMS messages. This is for security reasons. If the services is hacked it is not possible to send SMS messages to random phones. Both Sender and Receiver accounts can be assigned to groups. This way it is possible to hide the Receiver accounts belonging to the family group from a user that is part of the friends group. BrijnSMS is a front-end to SMS Client and handles all SMS services supported by it.