Numerous CAD programs are on the market which vary in complexity and cost. In law enforcement, drafting systems are used to prepare diagrams, exhibits, charts, and even informational posters. Advanced CAD programs are especially useful in crime scene investigations. In one homicide case, for example, the lead crime scene investigator built a three- dimensional model of the scene to better document blood splatter throughout the residence. A considerable area of the floor used a hexagonal tile which would have been extremely tedious to draw by hand. The investigator selected a tile from a symbol library, determined the proper scale at which to print it, and produced a wall paper that could then be cut and pasted as the flooring. Various CAD applications are described that have changed the face of crime scene and traffic sketching. 1 figure