Ocular barriers and the poor water solubility of drug candidates present a number of problems for the development of ocular drug delivery systems. Recently, the emergence of lipid-based nanocarriers has provided a viable means of enhancing the bioavailability of ophthalmic formulations. A number of these formulations have been found to be clinically active and several others are currently undergoing clinical trials. In this review, the advantages of lipid-based nanocarriers as non-invasive topical ocular drug delivery systems are presented. Many systems, including emulsions, liposomes, cubosomes, niosomes and other lipid-based nanocarriers, are reviewed.