Implantable drug delivery devices, nondegradable reservoir or biodegradable types, have shown great prospects. These devices have revealed ostensible possibilities of advancement in several applications demanding onerous efforts in controlled and precise, highly localized liberation of decisive doses of drugs with fewer side effects and without direct medical intervention. Actively controlled devices are more propitious than passive release devices. This greater potentiality of active devices is because the drug delivery process can be controlled post-implantation and even by telemetry, involving automatic measurements and telecommunication. Dissenting from passive devices, they do not rely on the chemistry of degradation of specific materials in the premeditated region of the implant. Numerous implantable drug delivery devices have been reconnoitered for use in chronic and terminal diseases. Diabetes, osteoporosis, and cancer are a few such examples. Robotic capsules are small, pill-sized devices that can be swallowed to perform diagnosis and drug delivery.