An interpenetrating polymer network (IPN) is any material containing two polymers, each in network form. An IPN is a combination of at least two polymers, and IPN can produce synergistic effect by sharing the properties of both the polymers consequently avoiding the limitations of natural as well as synthetic polymers. The present review discusses various types of IPN. Various methods of preparation and advantages on IPN are elaborated. The concepts of high swelling capacity, specificity and sensitivity of IPN play an important role in targeting delivery of drugs. IPN has various advantages as a biomaterial and is widely used as carrier systems for delivery of the short biological half life drugs.