About half of the drug entities or candidates are poorly water-soluble.How to improve their dissolution and oral bioavailability remains to be one of the leading challenges in the pharmaceutical industries.Besides many traditional solubilization techniques, nanoscale drug delivery systems show significant potential in not only solubilization but also oral absorption enhancement.Those lipid-based nanocarriers are unique in their absorption enhancing mechanisms.The successful marketing of several lipid-based drug delivery products draws more attention from both industries and academics.