HI, yes you can merge gedcoms. I have done it several times, working form laptop to Iphone app. Sometimes it results in duplicates if the names are not EXACT. When you open you Reunion program Look on hte tool bar for the MANUAL icon and click on tht. search for Merge Gedcoms, or just merge and it will tell you how to do it. I run a "Match and Merge" (also expalined in the manual) frequently to make sure I have not entered duplicate people or have a few "orphans" running around in my Files. HTH (Hope this helps) Happy searching!!