Check out this recent article published in The Australian:
Combining good works with your overseas travel seems like a perfectly altruistic adventure. Alas “voluntourism” is a road with twists and shocking turns, the worst being the discovery that tourists’ generous empathy for orphans created a child-trafficking racket in several countries. It’s now recognised that volunteering in orphanages feeds exploitation of children. It has been abolished by many organisations, is discouraged by the Australian government and soon may be banned…