A polymer stereocomplex is defined as a stereoselective interaction between two complementing stereoregular polymers, that interlock and form a new composite, demonstrating altered physical properties in comparison to the parent polymers. The main interactions, resulting in the complexation, are suggested to rely on stereoselective van der Waals forces. This review focuses mainly on homo-stereocomplexes of poly(methyl methacrylate) homo- and block-copolymers, which are non-degradable biopolymers, and biodegradable poly(lactic acid) (PLA) homo- and block-copolymers and hetero-stereocomplexes between D-configured PLA and L-configured peptides. Topics including physical methods for characterization and visualization and the use as matrices for controlled release, tissue engineering or other biomedical purposes, are discussed for the different stereocomplexes.