It is process of transferring a pharmaceutical compound into the body for providing therapeutic effect to the body. It is integrated with dosage form and route of administration. Common routes of administration of drugs are through the mouth, skin, Trans mucosal and inhalation routes. The use of nanotechnology in drug development is the developing process where the nanoparticles used to deliver the drug to the particular cell which is diseased. By this technology the particles which are engineered in such a way that they can attract to the diseased cell and allows treatment to the particular cell directly. Through this unique technique can minimize the damage of healthy cells in the body. Drug delivery refers to approaches, formulations, and transporting a drug compound in the body as needed to administer a safety and therapeutic effect. It may induces site-targeting within the body, or it may involve facilitating systemic pharmacokinetic and pharmacodynamic properties i.e., administration, metabolism, excretion etc. In target drug delivery system the drug is delivered to the patient concentrating that the drug should release in the targeted sites of the body. This increases the safety and reduces the side effects by decreasing the release of drug concentration in not targeted sites.