Adding comments when changing an item's state is especially useful when a submitter wants to send special instructions to the review team, when site managers and reviewers need to explain why they are rejecting an item submitted for publication, or to explain why an item is being taken off the site or sent to the archive queue.

To add comments, choose 'Advanced...' from the transition drop-down menu by clicking the down arrow next to the current state.  Scroll down to the comments field, and add any special notes or instructions.  Under 'Change State', choose the transition you would like to execute, and click the 'Save' button.

Comments can be viewed by using the history button (the plus sign in the square) next to the last modified date. The expanded comment history looks like this: