The RSoft CAD Environment™ is the core program of the RSoft Photonic Device Tools, and allows researchers and engineers to create systems for the design of waveguide devices, optical circuits, and other photonic devices. It acts as a control program for RSoft's passive device modules, including BeamPROP, FullWAVE, BandSOLVE, GratingMOD, DiffractMOD, FemSIM, and ModePROP, and defines the important input required by these programs: the material properties and structural geometry of the device to be studied.