Stem cells are cells that can proliferate with almost unlimitedpotential, maintaining a pool of growing and dividing cells, with the addedability that some cells can differentiate into specific cell types. Stem cellsare present in all self-reviewing tissue and have unique characteristics thatenable them to control cell replacement during homeostasis and tissuerepair.The ocular surface is made up of two distinct types of epithelial cells,constituting the conjunctival and corneal epithelia. These epithlia arestratified, sequamous and non keratinized. Although anatomicallycontinuous with each other at the corneoscleral limbus.Limbal stem cells have been localized to the palisades of Vogt in thecorneal limbus. The microenvironment of the limbus is considered to beimportant in maintaining stemness of stem cells. They also act as “barrier”to conjunctival epithelial cells and prevent them from migrating on to thecorneal surface.In certain pathologic conditions, the limbal stem cells may bedestroyed partially or completely resulting in varying degree of stem celldeficiency with its characteristic clinical features. These include“conjunctivalization” of the cornea with vascularization, appearance ofgoblet cells and irregular and unstable epithelium.Limbal stem cell deficiency disorders are divided into two majorcategories. Category I diseases are characterized by having clearpathogenic cause identifiable from past history which has destroyed thelimbal stem cell population. However, category II diseases exhibit gradual loss of limbal stem cellfunction overtime which speculated that limbal stem cell function can bemodulated by developmental, neuronal, vascular and inflammatory factorsin the limbal stromal microenvironment.The management of ocular surface disorders by limbal stem celltransplantation procedures which are classified based on the origin of thetissue whether being auto graft or an allograft. The different surgicaltechniques used in limbal stem cell transplantation are limbal auto graft,living relative conjunctival allograft, keratolimbal allograft, the adjunctiveuse of amniotic membrane and ex-vivo expanded transplantationRetinal stem cells are multipotent central nervous system precursorsthat give rise to the retina during the course of development. Retinal stemcells are present in embryonic eye cup of all vertebrate species.The approaches to treat degenerative changes of the retina due todiseases or injury are categorized into an ex vivo and in vivo Theseapproaches may be applicable, For treating degenerative changes in theretina associated with diseases such as retinitis pigmentosa, Age relatedmacular degeneration and Glaucoma.But there is a barrier to use of embryonic retinal Stem cell/Progenitors that may make their clinical use rather impractical. For thesereasons there are attempts in various labs to identify alternate sources(ocular-extra ocular) for generating retinal cells and study the putativemechanism that regulate the efficiency and Fidelity of retinaldifferentiation from heterologous cells.