I've recently gotten caught up in the Public vs Private Tree debate because someone had incorporated a large piece of my personal/orignal research into their own tree and corrupted it, causing me not a few headaches everytime I search for 'hints' in that line. I'd like to hear some opinions on an idea I've had to get Ancestry to replace the "save this person to your tree" link, which is shown when viewing another person's family tree, with a "request permission to save this person to your tree" link. Clicking the link would send a message to the orignal researcher requesting permission to add their data to your tree and also grant that researcher viewing access to yours. This would allow the original researcher the opportunity to view your data and determine if adding their (the original researcher's) data would be approriate/accurate. This change won't keep anyone from manually typing in information from other people's research; however, it should give the original researcher greater control, without privatizing the data, of how their work is incorporated into another's tree by making it far harder for "harvesters" (people more interested in bragging rights than they are about accuracy) to grab other people's research and incorporate it into their own without permission.