One type of cheating takes place before the test or exam. It involves getting illegal access to information about the exam. This can for the most part be prevented by making sure that copies of the exam and its drafts are not made accessible to people who should not have access to the material. To ensure this, material related to the exam should not be left on office desks or in wastebaskets. Aside from locking up exam material, making the material hard to find can be a useful extra precaution.

A second type of cheating is just plain copying from the work of neighbouring students in the examination room. This can be hard to avoid and hard to detect in crowded examination halls, particularly in sloping lecture halls, where students may be able to see the work of several other students without being obvious about it. This kind of cheating is particularly easy in the case of multiple-choice questions or questions for which the answer is a number, a formula or a diagram. It is less likely to be a problem in exams requiring essay answers. Sometimes a student will deliberately permit another student to see his or her work. Students who consciously provide information to other students are also being academically dishonest.

There are some ways to minimize copying. Students should be seated as far apart as the room allows. Also, it is better to have student directly behind one another than a bit to the side. In sloping lecture halls, an invigilator standing at the front of the room and looking towards the students can see whether the eyes of the students are looking in an appropriate direction. It helps to require students to remove hats that might hide wandering eyes. Another useful technique is to have two or more versions of the exam distributed in alternate seats, so that students cannot easily see other copies of their version of the exam. For example, different versions of a multiple-choice question could be obtained by rearranging the order of the questions, or of the answers for each question. In the interests of prevention, it would be appropriate to indicate in advance that there are several versions of the exam.

During an exam, if there is reason to suspect that a student is copying from another student, but the invigilator is not be completely sure, it may be appropriate to ask the student to move to another seat where copying is not possible. This should be done in a way that does not cause disruption for other students. It also can be useful to have another invigilator assess the situation.

Another type of cheating involves bringing information into the exam room before or during an exam. This could involve smuggling in notes, either at the start of the exam or in connection with a trip to the washroom. It also could involve using a cell phone or other communication device. It is clear that such devices should not be allowed. To minimize the possibility of a student bringing in exam booklets containing information, one could mark the official booklets for the exam in some way.

Some students cheat by arranging for another person to write an exam in their place. The main preventative measure here is to check identification and signatures carefully. If all the students are known to the instructor, such cheating is less likely to occur, but for big classes, this sort of cheating may be hard to prevent. Photographs are not always clear, especially if the hairstyle or the glasses of the person has changed. As in the case of copying from another student, it would be appropriate to ask students to remove hats that hide their faces.

Another type of cheating takes place after the exam. A student might attempt to change the answer on a graded question and then, without acknowledging the changes, ask the instructor to grade the exam again. The alteration may involve changing an answer or adding additional material. The former problem can be minimized by asking students to write their answers in ink. The problem of added material can be minimized by drawing lines with red ink around the written material or just under the bottom part of an answer, so that it would be hard to add much material without crossing the line or curve. If there is reason to suspect that an answer has been altered after having been returned to the student, it could be appropriate to make a copy of later tests written by the same student, so that hard evidence can be obtained.

It is obviously important for invigilators to take their invigilation responsibilities seriously, and to watch for activities that suggest cheating. In the interest of prevention, it is important for students to know in advance that cheating of any type is not acceptable, and that confirmed cases of cheating will result in penalties. It is also very important that students know exactly what constitutes cheating. The rules should be clearly defined. The best way to do this is to include information with the material handed out at the beginning of the course.