I have a field I want to validate to contain one or more of only five specific words, ie, red, green, blue, white, yellow. The IN expression requires ONE of a list, but I want to be able to have more than one from the list, but always only from the list. Example of Color Field in: Record 1 - blue; Record 2 - blue green; Record 3 - (cannot enter black). What is the proper /macro/expression/formula to achieve this?