Nanotechnology in drug development revolutionizes the way drugs are delivered, targeted, and formulated. Nanoscale carriers like liposomes, dendrimers, and polymeric nanoparticles improve drug solubility, stability, and bioavailability. These systems enable controlled and sustained release, reducing dosing frequency and side effects. Nano carriers can be engineered to target specific tissues or cells, enhancing therapeutic precision. This is especially beneficial in cancer, infectious diseases, and neurological disorders. Surface modifications, such as PEGylating, help evade immune detection and prolong circulation time. Nanotechnology also aids in crossing biological barriers like the blood-brain barrier. Overall, it opens new frontiers for personalized and efficient drug therapies.