Depending on the version of Access you're using this can be very easy or just slightly more difficult. A2k and above gives you Conditional Formatting. Select the control, then from the format menu select Conditional Formatting... You can have up to 3 levels of conditions, each with their own formatting options. In A97 and lower you will need to use the OnFormat event to test for the condition and change the formatting, this will have to be done through code.