The petitioners, a dentist and his professional association, seek a writ of certiorari to quash an order that compelled disclosure of the names and addresses of all the dentist’s patients who received treatment from January 1, 1990, through the date of the interrogatory. Because we conclude it has not been shown that, at this stage of the respondent’s slander action, the requested discovery is either relevant or likely to lead to relevant discovery, we grant the petition, quash the trial court’s order, and remand for further proceedings.