I have a feeling that this should be a simple query, but I'm having a brain fart or something and can't figure out how to do it.

I have a table called movement, which has two fields called mov_end_dt and mov_org_cd. The mov_org_cd has multiple records in the table and I want to pick out the one that either has a null value in the mov_end_dt or has the latest date in that field.

For instance, say the data in the table is:

Code:
mov_org_cd    mov_org_dt
A00001        1/1/2008
A00001        2/1/2008
A00001        3/1/2008

A00002        4/1/2008
A00002        5/1/2008
A00002        NULL
The query should return 3/1/2008 for A00001 and NULL for A00002.

Can anyone give me a hand on how to pull that out? If a subquery is needed, each record does have an id field as a primary key as well.