The brain is one of the least accessible organs of the body, thus making the delivery of neurotherapeutics almost a challenge. Despite its relatively high nutrient support and exchange requirements, the uptake of any compound is strictly regulated by the blood brain barrier (BBB). As a consequence, BBB prevents effective treatment of many severe and life threatening diseases like brain cancer, epilepsy, Alzheimer's disease, schizophrenia etc. Numerous drug delivery strategies have been developed to circumvent this barrier. One such approach is the use of nanoparticles. Nanoparticles form solid, colloidal drug delivery system that consists of macromolecular materials in which the active principle is dissolved, entrapped or encapsulated or onto which the active principle is adsorbed or attached. Brain targeted polymeric nanoparticles have been found to increase the therapeutic efficacy and reduce the toxicity for a large number of drugs. By coating the nanoparticles with surfactants, higher concentrations of drugs can be delivered to the brain. The article presents various approaches used in design and delivery of nanoparticles to brain. It also reviews various patents that describe the use of nanoparticles to deliver various neurotherapeutics and neurodiagnostics to brain.