Selecting rows without a value for Date/Time columns

I'm running this query:

SELECT TOP 1 [DVD Copy].[Stock No]
FROM [DVD Copy]
WHERE [DVD Copy].[Catalogue No] =[Forms]![New Rental]![Catalogue No]
And [Issue Date] = Null;

Which works fine without the null check for Issue Date. I'm trying to select rows without a Date in the Issue Date column. Is Null the wrong kind of value to use for here?

If I remember access correctly, you can write:

and not isNull([Issue Date])

or write:

and [issue Date] is not null

instead of comparing to Null, because nothing equals null. (It's a weird paradox...)

On the subject of Nulls in Access (and in general) these articles by Access guru Allen Browne are unmatched in explaining things clearly:

• Nulls: Do I need them?
• Common Errors with Null