DSIAC subject matter experts performed a search of the open literature to locate new research pertaining to visible, infrared, and thermal signature management. The search focused on developments since 2018, when a previous summary was provided. Areas covered include manipulation of emissivity; reflectivity; adsorption; refraction and backscatter using multispectral camouflage materials; multilayered, cavity-coupled plasmonic systems; metamaterials; nanoparticles; carbon nanotubes; glass microspheres; nanofibers; electrochromatic fabric; metasurfaces; waveguides; and lenticular lens materials.