The peculiarities of modern linguistic situation of the modernized country are discussed in this article; unilateral and bilateral (parity or harmonious) bilingualism are marked; linguistic, psychological, sociological, educational and other aspects of bilingualism are justified. Multilingualism is characterized as the functioning of several (3 or more) languages in a multinational area and speaking several languages based on the needs of communication. There are several forms of multilingualism: a closely related and not closely related. Establishing two or more languages as state ones predetermines multilingualism as a mass phenomenon within certain society. Based on the analysis, authors provide conclusions on building a harmonious, socially effective bilingualism. (Kharisov F.F., Kharisova C.M. Bilingualism and multilingualism in a globalized society. Life Sci J 2014;11(11s):439-443) (ISSN:1097-8135). http://www.lifesciencesite.com. 99