Using the g_form.addOption methodIssue These are a few things to remember when working with addOption method Create an onChange client scriptYou would then need to use g_form.addOption(), on the category field to populate the choices.You would GlideRecord query the [sys_choice] or [question_choice] table for your choices, and an example of such a script can be found here towards the bottom of the article: ServiceNow Choice List Dependencies- To clear out the options from the Category field, you'll have to use either clearOptions or the removeOption() methods. You can read more about this on our developer's site: GlideForm - clearOptions(String fieldName)When you add the "none" choice back, are you using something like: g_form.addOption('subcategory', '' , '-- None --'); Also if the field is set to mandatory, you can turn it off by using the following client-side method: g_form.setMandatory(String fieldName, Boolean mandatory); GlideForm - setMandatory(String fieldName, Boolean mandatory)