Closing a conversation is like marking a task as completed. You should get into the habit of closing most messages after you send them unless you need to be the sole user or group notified when the patient responds.
Remember: you will always be able to see all previous interaction with the patient, regardless of when it is closed.
You can close conversations by assigning to the CLOSED List.
You can do this in the following ways:
1) Click "CTRL+SHIFT+C" on your keyboard
2) Click on the user or list name in the top right corner of the patient's conversation, and select "closed" from this list.
3) When there is no text in the message composer, you will see an "Assign" button (where the send button usually is) - click here to pull up a list of users, and select "Closed" to mark it as complete.