Abstract: This review investigates earthworms as reactors towards the development of designer earthworms for the decomposition of complex polymeric structures. Unit operation aspects pertaining to vermicomposting is least addressed or cited in literature, while a lack of models employing worms as composting agents recognizable as biological reactors is quite apparent. The process of isolation of complex macromolecular structures such as protein is also cumbersome and presents inaccuracies.