“…The ROP of cyclic phosphorus monomers is attractive, as the phosphorus ancillary unit enables easy functionalization and tuning of physical properties over a massive range (Scheme ). ,− Among the possible ancillary units, the phosphoesters are by far the most popular. The recent development of organocatalyzed ROP has been applied to phosphoesters with DBU, TBD, DBU/TU, and NHCs, providing well-controlled polymerizations. − The implementation of organocatalyzed ROP has enabled the recent exploration of polyphosphonates, polyphostones, and thionophosphoester, providing more hydrolysis, thermal, and photostable materials from less toxic starting materials. − …”