Have any of you done it? I've been considering it for a while but decided to read up a bit first and seems that it causes more harm than good. And yes, I do volunteer work locally too 
http://http://www.guardian.co.uk/commentisfree/2010/nov/14/orphans-cambodia-aids-holidays-madonna
http://http://www.guardian.co.uk/commentisfree/2010/nov/14/orphans-cambodia-aids-holidays-madonna