It's worth noting that the Red Cross generally ranks highly when it comes to efficiency (i.e., low overhead):<p><a href="http://www.charitywatch.org/toprated.html#humanserv" rel="nofollow">http://www.charitywatch.org/toprated.html#humanserv</a><p>Of course, this has a lot to do with economies of scale, and "low overhead" does not immediately imply "high impact per dollar."