Shift Scheduler is a Perl/CGI script for managing volunteer registration. It allows one or more administrative users to login to the backend and create events, jobs and shifts. Anyone can then access the frontend to sign up for shifts. The backend can also be used to send an automated email reminder to volunteers who have signed up for one or more shifts. The script allows for shifts that require multiple volunteers, and does not allow a volunteer to sign up for more than one of the spots in such a shift. It also does not allow more people than are needed to sign up for a shift. All data is stored in a database (tested with Postgres 8.2 and MySQL 5.0.38).