The invoice request screen should include the option to enter credits as well as debits. Or at the very least, allow for negative amounts to be entered in the debit column. Vendors do not always submit separate credit memos for items but include them on new invoices where the net invoice amount is still posisitve but there are credtis that need to be coded to accounts, and that is not possible given the fact that I cannot enter a credit to a g/l account from this screen.