The theory of social capital and the formation of migrant networks creates the social foundation for ethnic enclaves. Douglas Massey describes how migrant networks provide new immigrants with social capital that can be transferred to other tangible forms. As immigrants tend to cluster in close geographic spaces, they develop migrant networks—systems of interpersonal relations through which participants can exchange valuable resources and knowledge. Immigrants can capitalize on social interactions by transforming information into tangible resources, and thereby lower costs of migration. Information exchanged may include knowledge of employment opportunities, affordable housing, government assistance programs and helpful NGOs. Thus by stimulating social connections, ethnic enclaves generate a pool of intangible resources that help to promote the social and economic development of its members.