Courses may have prerequisites. These are requirements which must be completed before enrolling in a certain course. Types of prerequisites include instructor’s permission, certain scores on placement tests, previous coursework, and good standing in certain programs. Prerequisites are designed to help assure that the student has a reasonable chance of success in a course. Courses listed as prerequisites must either be completed with a “C” or better, or the student must have obtained the instructor’s written permission before taking the next level course. Instructor’s permission is usually required for courses in which there is limited laboratory space or equipment or in which specific skills are required.