Merging

You can merge workbooks that have been created from the same template.
When you merge workbooks, all changes made to the merged workbooks are merged into a master workbook.
You can only merge workbooks that have been saved with sharing turned on.

An alternative to sharing might be to distribute copies of a workbook and then merge these separate copies together.

At some point in sharing a workbook you will want to update the workbook to incorporate all the changes made to it by different users.
While file sharing is on, Excel automatically updates the changes made to the shared workbook whenever anyone saves the workbook with his or her changes.
If Excel identifies any cells in a workbook that contain conflicting changes (i.e. different users putting different values in the same cell). The Resolve Conflict dialog box will be displayed giving the user a choice about which one to accept.
SS - Resolve Conflict

After the last conflict the dialog box is closed and the changes to the workbook are saved.
When you share a workbook by turning on change tracking for a workbook (Tools > Track Changes) to turn off file sharing (Tools > Share Workbook) ??
An alternative to sharing a workbook is to distribute copies of it and then merge the changes afterwards.
The key to merging workbooks successfully is to have the "Change History" log turned on and each copy should be saved under a different filename.
1) Turning Change History on - (Tools > Share Workbook)
check - allow changes by more than one user at the same time
2) Save them with different filename using (File > Save As).

The change history will only be kept for 30 days (by default). This however can be changed on the Advanced tab of the Share Workbook dialog box.

Merging them Back

Open the original shared workbook into which you want to merge the changes / copies
The copies of the original workbook whose changes you want to merge must not be open in Excel and must have different file names.
(Tools > Compare and Merge Workbooks)
Display the "Select Files to Merge into Current Workbook" workbook
SS
Select the workbooks you want to merge

Click OK
You will be prompted to review or accept the changes
All changes are merged into the open workbook ?

The workbooks will be merged in the order which they appear in the dialog box.

This feature should not be used if you want to be able to decide which value to accept and which to reject.
All the values are just overwritten

The Consolidate feature can combine up to 255 worksheets from any number of workbooks.

You can use the Windows Briefcase to take a shared workbook along for mark-up, then merge the changes in your copy back into the original (Tools > Merge Workbooks)

After changing a workbook to a sharing workbook you can use (File > Save As) to make multiple copies of that workbook.
You can then send these different workbooks to different people and have them sent back to you at a later date.
After the workbooks have been returned you can merge these workbooks back with the original workbook.
Save all the shared workbooks in the same folder with the original workbook.
Open the original workbook and select (Tools > Compare and Merge Workbooks).
The workbook will be automatically saved.
Browse to the other copies of the workbook that you want to merge.
After the merge, all the changes will be recorded in the cell's history with the most recent showing.
Make sure that you have "All" selected in the "When" drop-down box on the (Tools > Track Changes > Highlight Changes) dialog box if you want to see where the merge takes placed.
Changes will need to be accepted or rejected.