If you have several users who need to work from the same workbook at the same time, familiarize yourself with Excel's Shared Workbook feature. This feature can be a lifesaver when workbooks must be updated by multiple users.

To use this feature, select Tools | Share Workbook, and Excel will allow multiple users to edit the workbook. You can set options that control when changes are updated and how to handle conflicting edits by different users. You can also choose to save updates when a user clicks Save, or you can specify a time interval for Excel to automatically save user updates. In the Share Workbook dialog box, you can decide how changes should be logged by the Track Changes feature, which integrates with workbook sharing. That way, you can see exactly what changes were made to cells, when sheets were added or deleted, how conflicting edits were resolved, etc. Users can also see the names of all the other users who have the workbook open for editing.