The concept of brain drain includes not only aphysical emigration of highly qualified persons from onecountry to another but also a transfer from one departmentof an organization to another, as well as any other loss ofskills and knowledge of one economic unit necessary foreconomic growth and development in favour of anothereconomic unit. Brian drain occurs as a result of the factorsof attraction and repulsion of migration of qualifiedspecialists, scientists and students. Three levels of thereason for brain can be distinguished: individual,organization, and state.Brain drain occurs in all countries of the world with avarying extent and character. In the economicallydeveloped countries more attention is given to the problemof brain drain. It has become an object of interest andresearch in these countries much earlier than in theeconomies of transition. This can be proven by a moreextensive and accurate statistics provided in differentsources, as well as the abundance of different research. InLithuania little analysis has been made on thisphenomenon. It is difficult to determine the extent of braindrain from Lithuania due to the lack of statistical data andsociological research. The article underlines that theemigration of highly educated specialists from Lithuaniamay have negative economic, social, cultural and evenpolitical effects on the development of the country.