Pretty simple question, I believe.
I know that I can specify a value of a field in a query entering some question between []
My question is how can I make a combo box listing the values of a table appear instead of a blank field to input the value desired?

Thanks in advance

If I understand you correctly you want to be able to make a choice from a list of values without a blank field appering in the list.

You a Listbox instead of a Combobox.
Use the Wizard to create the query on which the list of values is based.
After completion, the Rowsource Property of the listbox will contain this kind of statement:

= "SELECT DISTINCTROW [Table/Query]![Field] FROM [Table/Query]"

Greetings,

RV

Create a form that contains a combobox. Add a button to run the report. In the criteria of the report's query, reference the combobox name rather than a parameter name.

Forms!YourFormName!YourComboName