First thing I'd suggest: you need some way to uncheck the checkbox if it is disabled. Because players will make a mistake and check it by accident. If there's no way to undo it, that's bad. But on to the actual question: If you want the checkbox to remain visible, but disabled, two approaches come to mind: Use the CSS Swap Areas trick (see CSS Wizardry page): You have two checkboxes, one disabled, one not. The disabled one is hidden. When the checkbox is checked, the non-disabled checkbox is hidden, and the disabled one takes its place. The second method is a sheet worker: you check the checkboxes status when clicked. Using eventInfo (see wiki on sheet workers) you can get the previous state before being clicked. If the prev state is checked, it means the player is trying to uncheck the checkbox. So you have the sheetworker just recheck it. That way the player can never uncheck it.