Since the advent of analytical techniques and capabilities to measure particle sizes in nanometer ranges, there has been tremendous interest in the use of nanoparticles for more efficient methods of drug delivery. This expertly written guide addresses the scientific methodologies, formulation, processing, applications, recent trends, and emerging technologies in the research of nanoparticulate drug delivery systems (NPDDS). It extensively covers applications of NPDDS, including lipid nanoparticles for dermal applications, nanocarriers for the treatment of restenosis, ocular, central nervous system, and gastrointestinal applications, and use as an adjuvant for vaccine development.