I'm using this query: SELECT DPT_NameFROM DepartmentsORDER BY DPT_Name My input control has the same name as the parameter it is linked to (DepartmentList). The value column and visible column are both DPT_Name. This results in a multiple selection list with 44 [NULL] values, which happens to be the exact number of departments we have in the database. If I select one of the null values displayed and run the report, it functions as if the selected value were actually a valid department name. If I use this query: SELECT DPT_PK, DPT_NameFROM DepartmentsORDER BY DPT_Name ...and set the value column of my input control to DPT_Name, but set the visible columns to DPT_PK followed by DPT_Name, I get the exact results I am expecting, which is a list of all 44 primary keys paired with their corresponding department names (something like '2 | Cheese,' '1 | Grocery,' '3 | Mercantile,' etc.). If I take the department name out of the query and set up the input control to display only primary keys, the list functions as expected. Going back and doing the same thing with the DPT_Name column again results in a list of null values. As long as the first or only visible column contains integers, every visible column displays and functions properly. It seems strange that I need to do this at all, but for now I'm using it as a workaround until I can figure out what I'm doing wrong.