This book describes the overview of flavonoids - phospholipids complex. The complex is a lipid compatible molecular aggregates, where flavonoids and phospholipids are held together via weak intermolecular forces of interactions. This interaction of complex improves the biopharmaceutical attributes of flavonoids and/or Biopharmaceutical Classification System class II drugs. This book provides information about the preparation of complex, their optimization using Design of Experiments (DOE), their characterization, and pharmacokinetic analysis. Moreover, the added comprehensive information about complex will help the researcher, academician, and research scholar to design their project based on phospholipids complex technology.