Katherine:
In the form's On_Open event, set the locked property to True for all fields where you do not want the user to make changes.
In the Edit button's On_Click event change the locked property to False.
You should also add the locking routine to the form's On_Current event so that the fields are relocked when the user moves from record to record.
I generally use this procedure to lock all controls on the form except selection combos and navigation buttons. I put an Edit button on the form to unlock the controls and a Save button to explicity save the changes (I also include an Undo button to allow the use to cancel changes).
When the Edit button is clicked, I also disable all command and navigation buttons (except Save and Undo) until either the Save or Undo button is clicked.
This may be overkill, but I get paranoid about users messing with the data when they really don't intend to make changes.
Hope this helps.
Larry De Laruelle
larry1de@yahoo.com