Biodegradable aliphatic polyesters, in particular PLA-based materials derived from l-lactic and d-lactic acids, present growing interest for applications in the field of surgery, tissue repair and regeneration, as well as sustained drug delivery. Stereo-complexation allows improving the mechanical performance, thermal stability and hydrolytic resistance of PLA-based materials due to the peculiarly strong interaction between PLLA and PDLA sequences. These improvements mainly depend on the degree of stereo-complexation, a higher degree of stereo-complexation leading to larger improvements of material properties. Stereo-complexation provides a means of choice to develop novel applications for PLA-based materials, such as nanofibres, nanogels, nanotubes, microparticles, micelles and hydrogels. The applications include surgical implants, tissue engineering scaffolds and various controlled drug release systems. Among them, self-assembly micelles and hydrogels by stereo-complexation are particularly attractive for sustained delivery of anticancer drugs, proteins and peptides. Last but not least, the reduced cost of PLLA and PDLA from renewable resources could further enlarge the field of applications of stereo-complexed PLA to commercial polymeric materials.