Copying Civil 3D styles from one drawing to another or importing styles into an existing drawing from a tempale has been a tedious process in the past. Yes, you could do it, but the process was time consuming. Now in AutoCAD Civil 3D 2012, we finally have a quick and easy Import Style command. This command is found on the Manage tab of the ribbon on the Styles panel. Just run this command and you are asked to select the drawing or template that you would like to import the styles from. After selecting the desired source drawing or template you are presented with the dialog box below.
Here you are shown styles to be added (these are styles that do not currently exist in your drawing), styles to be deleted (these are styles that exist in your current drawing but do not exist in the source drawing or template) and styles to be updated (these are styles that exist in both the current drawing and the source drawing or template and will be updated to properties of the source drawing styles). This gives you complete control over exactly how each style is imported or if it is skipped. Finally there is a check box at the bottom of the dialog box to Import settings. This will allow you to import the Civil 3D settings from the source drawing or template.
This is a tool that many of us have been asking for in Civil 3D for a long time and I encourage you to give it a try next time you need to update the styles or settings in a drawing.