The closed bilayer phospholipid systems likely called liposomes, were first described in 1965 by Alec Bangham and soon were accepted as drug delivery systems. Work on liposomes by number of researchers led the technical advances. These advances have led to numerous clinical trials and studies in such diverse areas as the delivery of anti-cancer, anti-fungal and anti-biotic drugs, the delivery of gene medicines and drug delivery to site of action, long circulating PEGylated liposomes, triggered release liposomes and liposomes containing combinations of drugs. This review is a focus on recent advances and some of the relevant challenges faced in developing clinically relevant liposomal drug carriers. The main objective of pharmaceutical science is to design and develop dosage forms with fulfilling the therapeutic need of the patients effectively. The writing highlights all aspects of liposomes starting from compositions to therapeutic applications and strategies through preparation and characterization. It is discussed in-depth on the role of lipids in bioavailability, design of lipid based drug delivery systems, and understanding of morphological characteristic of liposomes etc. Lipids as carrier have the potential of providing endless opportunities due to their ability to enhance intestinal solubilization and absorption via selective lymphatic uptake of poorly bioavailable drugs. Their use provides improved pharmacokinetic properties, controlled or sustained release of drugs with less systemic toxicity. Liposomes, which emerged as the most relevant model for biological membranes and for understanding lipid biophysics, later became the most successful drug delivery system with more number of FDA approved products.
