When exporting to shape files , the fields of the dbf database are at full size. Full size meaning that a text field may have only a maximum of 10 characters in the field, but the field size will be 255. This lack of compression leads to very large dbf files. To reduce the dbf file size I normally open the file in Excel and Autofit the Columns. Before export, Autocad Map could scan the data and find the maximum length and set that length to the field size. Thanks, TC