Trainers have long relied on visuals to make their training more effective. This paper explores whether or not graphic design principles, commonly employed by trainers in presentations and Web-based training modules, influence the learning process. A review of the core works in the field of instructional design reveals that most of the principles espoused in the literature are based on the opinions of experts rather than on the results of empirical research. A further review of the literature was conducted to identify the origin of these principles. Using theories of visual cognition and adult learning as criteria, these studies were analyzed to determine whether the theory and methodology used translates to a training environment. The study concludes that while many of the older studies are based on empirical research, their findings may not be appropriate for today's trainer.