Polymer design from renewable sources or waste is a key research area in the circular bioeconomy. Phenols,terpenes, polyols, and vegetable oils are eligible raw materials for the manufacture of a variety of materials,including elastomers, plastics, hydrogels, and composites. Beyond their structural role, most natural compoundspossess intrinsic bioactivity, making them particularly attractive as feedstock for the development of bioactivemacromolecular systems for biomedical applications. By leveraging their chemical versatility and biologicalproperties, these bio-based polymers can be tailored for antimicrobial coatings, drug delivery systems, and otheradvanced therapeutic applications.In this talk, I will present key advances in the synthesis of functional polymers from natural feedstock [1-5],focusing on their application as coatings for medical devices (Figure 1) and as carriers for drug deliveryformulations. The use of natural phenols, including tyrosol, hydroxycaffeic acid and eugenol, to design bioactivepolymers with tunable antimicrobial and antioxidant properties will be explored. A crucial aspect of thisapproach is the development of macromolecules with intrinsic antimicrobial activity, which have emerged as aparticularly promising class of compounds for addressing antibiotic resistance. Also, the synthesis andfunctionalization of bio-based aliphatic polyesters will be presented highlighting their potential as carriers fordrug delivery.