How can we match a condition among 2 diff. tables?

Hi,

Consider the below...

table 'employee' with unique 'emp_id',
table 'salesorder' with 'emp_id' and unique 'sales_id'

Remember, both tables include some more different fields.

Now, i need to get the details of all employees who did
receive NONE of the salesorders. ie.. i wish to select the
records of table 'employee' whose 'emp_id' are not
there in table 'salesorder'.

I need to accompolish in a single query!

Thankx in advance.

Regards,
Bhuvaneswar.