I need to know the best way to share our water mapping with an outside engineering firm who is contracted to build a water model for us. Our GIS is very new and recently converted from older Autocad mapping. None of the line-work has pipe size, material, or other attributes yet (just blank fields) and the company building our model will be adding that as they go. What is the best way to share our GIS with them so that the attribute information they add can be synced back into our GIS afterward? Should I just create and send them a shp file? Is this where replica database stuff comes into play? I may be making edits and cleaning up the errors from the conversion from our old autocad mapping at the same time they are doing their thing. I'm completely new to ESRI's way of thinking but I know there is a way to share data and have changes synced back, but I don't know where to look. Any and all help would be appreciated.