CAESAR will not allow you to register for two courses if there is an overlap in the course meeting times (including the labs or discussion sections, if any). If there are circumstances that would allow you to fully participate in both courses, even with the time overlap, you can get registered if both professors will sanction this. There is a Registration Time Conflict Permission form available on the Registrar’s website at http://www.registrar.northwestern.edu/registration/time_conflicts.html. You will need to get the signatures of both professors on this form and then bring it to the Student Resource Center in the Music and Communication Building, room 5-134. Along with the time conflict form, you will also need to submit an Add/Drop Registration Exception form giving the details of the class you still need to add (including subject, course number, section, etc.).