Converting acad drawing from Ft to mm

Does any one knows how to convert the drawing drawn in ft/ inches to meters/mm units. All the Civil/ architectural drawings are in ft/ inch. We prepare the drawing in mm units. At present we are using scale factor to convert the drawing. Is there any other simple solution?

If you go into 'Format' then select 'Units' then use the drop down box to select 'Decimal'
Then choose the 'Feet Inches' in the 'Drag & Drop' box

Now all you have to do is select the drawing on the Model Space and drag it to a new area.

Many thanks