Abstract: Biodegradable, radio-opaque polyesters and poly(ester amides) are described herein. The polyesters contain a plurality of radio-opaque agents or radio-opaque agent-containing moieties that are covalently bound along or from the polymer backbone. The agents/moieties may be bound to the termini of the polymer provided they are bound within the polyester backbone as well. The polyester can be aliphatic or aromatic. The polyester and poly(ester amide) is substituted with a plurality of radio-opaque graft agents or prepared from an appropriate radio-opaque monomer agent. The materials can be used for any application where a radio-opaque material is desired or necessary. The materials can be used to form, in whole or in part, a medical device, or coating thereon or therein.