Poly-ε-caprolactone due to favorable properties including biocompatibiity, miscibility and controlled degradation is promising material for long term drug-delivery devices preparation, especially in blend with other polymers. Commercially available polymer is synthesized without considering this way of utilization, and may contain potentially toxic residues of compounds used during polymerization process. Therefore, we attempt to summarize in this work available methods for synthesis of poly-ε-caprolactone using nontoxic reactants. The product properties important for polymer drug delivery system such as number average molecular weight and polydyspersity index (PDI) were included. Also we present known methods for purification of the polymer from catalyst residues, and other methods that may improve process of polymerization catalyzed by less active compounds.