One of the things that has given me the most cause for thought and concern in the past, and was reiterated by Professor Griggs, was the conflict that arises when implementing large scale changes that will have some sort of immediate disruptive or negative effects on the local population. It is a difficult position to be in when you have the technology, means and intention to aid some problem, but there are temporary downsides. How does one tread the line between overstepping bounds, being presumptuous and assuming about the needs and desires versus contributing a large-scale human or environment-centered benefit.
The point of constant and large-scale communication with the local people, infrastructure and contacts is, I think, a very important one. Making a collective, as opposed to executive or even governmental decision can facilitate the acceptance by the local peoples, as well as a dedication to its success. Looking deeply at cultural issues is clearly incredibly important.