Around 50 UK tour operators have been contacted by Tourism Concern urging them to stop sending volunteers to overseas orphanages.
The campaign and charity group wrote to the companies last year and will be chasing them up later this month to make sure they have taken action.
If not, their names will be published on Tourism Concern’s website.
"This is a difficult campaign because many volunteers and tourists believe that they are doing good – and it is difficult not to be moved by children in need," said executive director Mark Watson.
"However in Nepal children are literally being stolen from their parents by orphanages who are using them as a commodity. In Cambodia the number of orphans have halved and yet the number of orphanages has doubled – 75% of children in these institutions are not in fact orphans.
"In Ghana the figure is as high as 90%. In sub-Saharan Africa more than 80% of ‘orphans’ have a surviving parent."
Meanwhile in South Africa, said Watson, researchers have found that the perception of an "AIDS orphan crisis", combined with voluntourism, has "fostered a potentially high-risk situation for already vulnerable young children in the region".
