Here's an excerpt of an interesting Overseas Indian Affairs Ministry paper regarding Indian diaspora:

In the theatre of development, the competitiveness and growth of an economy is determined by its capacity to acquire and apply new knowledge. In a rapidly globalizing world, learning new ways of doing things depends in no small measure on the ability to integrate with the larger world outside. We live in a world in which the free movement of goods and capital across borders is seen as a virtue. Arguably, it is seen to reinforce the principle of competitive advantage and help spur savings, investment and demand. What is less recognised is that International migration of human capital: the movement of knowledge, talent and skills across borders is central to learning and development.

The emergence of significant Diasporas has in recent years brought into sharp focus two key facts. First, there is a large expatriate population of skilled people from emerging economies in the developed world. Second, overseas communities can constitute a significant resource for the development of the countries of origin. The movement of the high skilled and low skilled workers from less to more developed economies and back opens several new opportunities for development. To view the Diaspora only through the looking glass of remittances and financial flows is to take a myopic view. Not all expatriates need to be investors and their development impact measured only in terms of financial contributions to the home country.

An overseas community can and does serve as an important 'bridge' to access knowledge, expertise, resources and markets for the development of the country of origin. The success of this bridge is often predicated upon two conditions: the ability of the Diaspora to develop and project a coherent, intrinsically motivated and progressive identity and the capacity of the home country to establish conditions and institutions for sustainable, symbiotic and mutually rewarding engagement. Home countries are now beginning to recognise the need to pursue and promote the dynamic of the Diaspora and development.

http://moia.gov.in/writereaddata/pdf/Strategic_Plan.pdf