A modal dialog box is an interaction with the user, such as a form to be filled in or a statement to be acknowledged, that pops up in its own window on top of the application. The user cannot continue in the application without processing the form or dismissing the modal dialog box. A flow action provides the section or sections containing the form fields that the user must complete. When the user submits the form, the system updates the work item and the modal dialog closes. The user can then continue working with the main screen.

To ensure accurate server processing of a modal dialog, use auto-generated controls. If a modal dialog box is configured with an action on a work item based on an event, the modal dialog box does not roll back the changes if the modal dialog box is canceled or dismissed.