A medical device with a therapeutic agent-releasing polymer coating. The medical device is provided by a method that comprises: (a) attaching at least one reactive species to a medical device surface, which reactive species leads to chain growth polymerization in the presence of monomer; (b) contacting the reactive species with at least one monomer species, thereby forming a polymer coating on the surface of the medical device; and (c) providing at least one therapeutic agent within the polymer coating. The therapeutic agent may be incorporated during formation of the polymer coating or after formation of the polymer coating. The at least one reactive species can comprise, for example, a free radical species, a carbanion species, a carbocation species, a Ziegler-Natta polymerization complex, a metallocene complex, and/or an atom transfer radical polymerization initiator. Alternatively, the medical device is provided by a process comprising: (a) immobilizing least one polymerization catalyst at a medical device surface, which polymerization catalyst leads to polymerization in the presence of monomer; (b) contacting the medical device surface with at least one monomer species, thereby forming a polymer coating at the surface of the medical device; and (c) providing at least one therapeutic agent within the polymer coating.