Considering the many disciplines involved in creating the settings for a film, it's not surprising that art directors should come from varied backgrounds. More significant that ther differences, however, are their commonalities. An artist's background and training are the most obvious requirements. Therefore, an ability to share ideas by way of sketches is an expected attribute of motion-picture art directors. An understanfing of color, line, form, composition, and perspective is essential. This training plus a knowledge of history and a sense of the appropriate are the touchestones of the profession.