Having access to view a credit card is only necessary at certain points during an interaction with a customer.  In most cases the number is only needed to be visible when entering, changing or confirming it while actually speaking with a customer.  When entering a new order, by default, the credit card number is unmasked for the entire duration of the visit to the order entry page.  However, there is a setting to mask the card after it has been captured.  To do this, navigate to Company Data -> Company -> System Preferences. Click the edit pencil to the left of the Company Name to launch the Edit System Preferences window. Click the System/Continuitys tab, then click where it says "More options" in the "Edit default system information" section. Finally choose one of the Mask options in the "Order Entry screen payment fields mode" drop down menu.  The dropdown supports 3 options as follows:

1) Default - This option will display the credit card for the entire time that the order entry page is open

2) Mask Fields - This option will display the first digit and the last 4 digits after the card is captured

3) Mask plus popup - This option will pop up a new dialog to capture the payment information.  The number will be visible in the popup, but once captured, the popup will go away and the card information will be masked as in option 2 above.