Once they process the record, the key field is changed slightly to take it off of their screen and put it on the screen of the person farther down the data entry process. As a serious designer, you should interview the data entry person for each area. For your interviews document as much as possible. It may be a good idea to flowchart out the users work flow and get them to approve it. If you get in the habit of flowcharting all the areas together, you can later include them in master flowchart document.
Flowcharts are one of the best friends of a database designer.
As you work on these sections, it's also a good time to work on the access documentation. You should define their access level and work on the password scheme accordingly. Password documentation is a great asset on large projects with multiple users. Superior password documentation can help you with this. I have found that password documentation along with a good macro utility can help make password changes a breeze with almost any level of complex database.