The numerous archaeological investigations conducted in the last few years with the aid of aerial photography provide us with much material for reflecting on the importance of this tool, which is now fundamental in regional topographical studies, and an opportunity to restate some of the practice’s basic concepts. With its many applications, aerial photography represents one of the greatest sources of useful material for studies in this sector. A correct assessment of the question of method obliges us to consider aerial photography as a source of data from which to draw a seemingly infinite amount of information in the course of a regional topographical investigation.