In the forefront of new formulating studies is that of preparing solid molding compounds retaining complete peroxide curing response. The solid systems can be attained by virtue of the unsaturated polyester-monomer or polyester-alkyd crystallizability or by reactive filler modification to give solid powder or granular-type molding compounds. The formulating of these systems to include low profile and low shrink properties has been and is being actively pursued. The potential for continuous processing and continuous utilization via injection and transfer molding is most exciting.