SQL:Remove Duplicates

DELETE FROM [ssi_tbl_NameAddress]

WHERE  control NOT IN (SELECT MAX(control)

                  FROM   [ssi_tbl_NameAddress]

                  GROUP  BY Lname,fname 

                  /*Even if ID is not null-able SQL Server treats MAX(ID) as potentially

                    nullable. Because of semantics of NOT IN (NULL) including the clause

                    below can simplify the plan*/

                  HAVING MAX(control) IS NOT NULL)