I'm creating a timesheet form and want to be able to populate a list of job
codes specifically by client.
For example, in the "Client" Column you select Client X from a list. The
"Job Code" Column would then produce the drop down list specifically related
to Client X. If in the "Client" Column I selected Client Y, the "Job Code"
Column would then produce the specific job codes related to Client Y.

There may be a much simpler alternative- any help would be appreciated.