Emerging as a de facto standard over the last decade, OptiGrating has delivered powerful and user friendly design software for modeling integrated and fiber optic devices that incorporate optical gratings. OptiGrating uses the Coupled Mode Theory to model the light and enable analysis and synthesis of gratings. A complex grating is approximated by a sequence of uniform segments, and analyzed by connecting the segments with the well-known Transfer Matrix Method. This gives the designer the information needed to test and optimize grating designs.