Liposomes were investigated for a long time as nanocarriers to target drugs to their sites of actions and to reduce toxicity. The unique structure of liposomes which is similar to the cellular phospholipids is considered as being an advantage to such delivery systems. Both hydrophilic and hydrophobic drugs can be encapsulated into the liposomes for delivery of a wide range of drugs such as anticancer drugs and antiinfective drugs used to treat tuberculosis and hepatitis. Liposomes can also be considered to delivery nutritional supplements such as vitamin C and vitamin D. Types of liposomes, lyophilization, advantages, disadvantages, challenges and immungenicity have been discussed.