As Lauren says the responses ...

As Lauren says the responses that focus on partnership are key.  Having said that, the hard thing is to understand the political and social context of the countries. A governments priority for communities requiring interventions may be influenced by politics or economic drivers. NGOs may have particular targets in terms of community structure or geography. We have found in the past that communities with unfavourable hydrology/hydrogeology can fall though the gaps because no-one wants to risk failure, even though they may have a high level of 'need'.

I would think the best thing you can do is define your own goals clearly -  in terms of technology, scale and issues like poverty -  and then look ,with partners, for communities that fit your own mission and ethos. If you  aren't clear about what you can deliver, and who you want to deliver it to, then it will be hard to enter effective dialogue.