Some groups may pursue a single policy objective - for example access to AIDS drugs in developing countries or press freedom.
Others will pursue more sweeping policy goals such as poverty eradication or human rights protection.
However, one characteristic these diverse organizations share is that their non-profit status means they are not hindered by short-term financial objectives.
Accordingly, they are able to devote themselves to issues which occur across longer time horizons, such as climate change, malaria prevention or a global ban on landmines.
Some are highly sophisticated, media-savvy organizations like Friends of the Earth and WWF; others are tiny, grassroots collectives, never destined to be household names.
Although it is often assumed that NGOs are charities or enjoy non-profit status, some NGOs are profit-making organizations such as cooperatives or groups which lobby on behalf of profit-driven interests.
Non-governmental organizations (NGOs) have played a major role in pushing for sustainable development at the international level.
Campaigning groups have been key drivers of inter-governmental negotiations, ranging from the regulation of hazardous wastes to a global ban on land mines and the elimination of slavery.
Such a stakeholder approach takes into account the effects of business activity - not just on shareholders, but on customers, employees, communities and other interested groups.
There are many visible manifestations of this shift.