Proper positioning and sizing of windows are essential for supplying sufficient amounts of daylight into a building. On the other hand, windows are often the source of excessive insolation causing glare and overheating, which have negative impact on the energy performance of a building, and most importantly - on the comfort and well-being of users. Development of tools for simulation of daylight and optimization of shading has already commenced in the 1970s. Nevertheless, none of the available design tools can naturally handle free-form apertures in a free-form surface (FFS) of a building envelope. This chapter presents Shade-Z, SZ for short, an intuitive design aid. SZ is intended for architects to be used at any, especially the early stages of design to ensure proper shading from undesirable insolation. The input for SZ are: the geometrical data of given FFS, geographical location, time-zone, required annual periods and hours for both: allowing and blocking direct sunbeams. SZ automatically detects the apertures and generates the geometry of static shading. The algorithm is explained and illustrated with an example of a free-form aperture in FFS located in Warsaw, Poland.