query using a date field that isn't set

Hi all,

I've got a SQL problem that's stumping me. I have an employee table with a
field labeled:

Emp_terminated DATE

Obviously, some employees in this table won't have this field set. I want a
query to select only employees without this field being set, ie., only
current employees. I've got the inverse working by using:

SELECT * FROM employee WHERE ISFINITE(emp_terminated);

And that gives me all the old employees (where the field has a value), but
for the life of me, I can't figure out the syntax to use for employees that
haven't been terminated or quit. Everything I've tried returns no rows.

Anybody?

--

John