An NGO is a non-profit association that functions outside institutionalized political structures and pursues its target issues by lobbying, persuasion or direct action. The term "NGO" typically refers to social, cultural, legal and environmental advocacy groups having non - commercial goals.
Twentieth century globalization gave NGO's a whole new lease because many problems arose that could not be solved within a nation. International treaties and organizations such as World Trade Organization were considered biased towards capitalist interests. NGOs lay emphasis on humanitarian issues, developmental aid and sustainable development which helped in counterbalancing the capitalist trend. A prominent example of this is the World Social Forum, a rival convention to the World Economic Forum held annually in Davos, Switzerland. The fifth World Social Forum in Porto Alagre, Brazil, in January 2005 was attended by representatives from more than 1,000 NGOs. 
There are three stages or generations of NGO evolution described in "Three Generations of Voluntary Development Action" (Korten, 1990). A first generation NGO is the typical development NGO that focused on relief and welfare and delivers its services directly to its beneficiaries. These NGOs notice immediate need and respond to them spontaneously. Common services offered by them are food, shelter and health services. The second generation NGO's are involved primarily in small scale, self reliant and local development. At this stage NGOs build the capacities of local communities to meet their needs through 'self reliant local action'. The third generation NGOs are referred to as 'sustainable system development' as they attempt to advance changes in policies and institutions at local , national ,as well as international level by moving away from their operational service providing role towards a catalytic role. At this stage the NGO has said to be evolved from a relief NGO to a developmental NGO (1).
It is important for NGOs to scale up from time to time to increase their impact and efficiency. Peter Uvin et al developed taxonomy of scaling-up practices and tested it in the light of the experience of 5 actual organizations and added more information to their initial list of possible paths to scaling-up and substantiating their impact.
In their study of the Indian NGOs, the authors focus on 4 types of scaling-up strategies.
Expanding Coverage and Size is probably the most evident form of scaling-up according to the authors. This involves increasing the number of employees, managing larger budgets, covering a larger number of beneficiaries in a larger geographical area and as a result becoming a larger organization. In Uvin's previous research, this kind of scaling-up was called "quantitative" scaling-up. After an initial period of rapid growth, some of the NGOs began to take concrete measures to stop growing or even "downsize." While this pattern was not universal, it appears that many NGOs fear becoming overly bureaucratic and unresponsive if they get too big.
Increasing Activities: there are 2 ways of increasing impact through increasing activities:
diversification or horizontal integration: this is simply the expansion in the number and diversity of the organization's activities,
vertical integration: this is when an organization adds activities that "feed into" their current activities (upstream integration) or are associated with