Ring-opening polymerizations of heterobicyclic compounds such as bicyclic acetals, bicyclic oxalactones, and bicyclic oxalactams often proceed stereospecifically, due to their rigid bulky structures having two or more asymmetric centers as well as due to the stereoelectronic effect of the heteroatoms. The polymers derived form these heterobicyclic compounds generally contain heterocycles in their main chains and are expected to exhibit desirable properties and/or specific functions. Recent progress in this field, particularly in the following three subjects is described in this review.1. Stereoregulation in cationic polymerization of bicyclic acetals in relation to structurally controlled synthesis of polysaccharides.2. Highly selective cyclooligomerization of bicyclic oxalactones to macrocyclic oligoesters having a chiral cavity.3. Ring-opening polymerizations of novel heterobicyclic compounds aimed at designing specialty polymers.