The mapping screen tells you “where” in your database the import file data will populate. The left side shows the Bloomerang field, while the right side shows the column title from your import file. READ THIS VERY CAREFULLY AND SLOWLY! It needs to be exactly correct, and all column title fields must be mapped to Bloomerang fields. This may require some manual mapping (by clicking on “Add Another Field” at the bottom of the mapping screen). If the First Name Bloomerang field is mapped to a column in your file titled “Name” (and containing last names only), those last names will be imported into the database in the First Name field (which is obviously undesirable). Once a file is imported into Bloomerang, there is no way to undo it besides manually deleting the entries or paying for a data services fee. Bloomerang will attempt to auto-map the columns as accurately as possible, but much of this depends on how you name your column headers. It’s critical that each field is mapped appropriately.