Abstract Introduction and Historical Outline Crystal Structure and Morphology Poly([R]‐3‐hydroxybutyrate) Poly([R]‐3‐hydroxybutyrate) copolymers Poly([R]‐3‐hydroxyvalerate) Poly(4‐hydroxybutyrate) Poly(β‐propiolactone) Poly(l‐lactic acid) Poly(ɛ‐caprolactone) Poly(ethylene succinate) Poly(ethylene adipate) Poly(tetramethylene succinate) Poly(tetramethylene adipate) Biodegradation of Single Crystals Poly([R]‐3‐hydroxybutyrate) and its Copolymers Poly(ethylene succinate) Poly(l‐lactic acid) Other Aliphatic Polyesters and Chemical Hydrolyses Outlook and Perspectives Acknowledgements