11-14 September, 2005, Denver, CO, USA. Visual Surveillance is now commonplace in modern societies. Generally, the layout of observers in artificial visual surveillance (e.g., CCTV camera) involves an iterative, manual and gut-feel process of trying various layouts until a satisfactory solution has been found. This paper proposes how a GIS, can be used to identify the optimal number and locations of observers, ensuring complete visual coverage using an automated technique, namely Rank and Overlap Elimination (ROPE). The ROPE technique is a greedy-search method, which iteratively selects the most visibly dominant observer with minimum overlapping vistas. The paper also proposes measurements to characterise the shape of open spaces, relevant in assessing natural surveillance. The paper demonstrates an extension, called Isovist Analyst, to the popular ArcView for planning artificial and natural surveillance in indoor and outdoor open spaces, with arbitrary geometry and topology
