Practice directives may not derogate from legislation that has binding force. A Judge President's power under section 7(1) of the Superior Courts Act to establish circuit courts and alter their boundaries does not extend to the power to determine or alter the jurisdictional areas of Divisions, which power is reserved exclusively to the Minister under section 6(3) of the Superior Courts Act. Circuit courts established under section 7(1) are not self-standing Divisions but remain circuit courts of the parent Division, creating concurrent jurisdiction with the main Division. A practice directive that purports to oust the statutory jurisdiction of a Division is ultra vires and invalid. Where a court has jurisdiction under section 21 of the Superior Courts Act, that jurisdiction cannot be removed by a practice directive. Until the Minister publishes a notice under section 6(3) establishing a new Division, the parent Division retains its jurisdiction over the area. Where a preliminary point is upheld without the merits being considered, the appropriate order is to strike the matter off the roll, not to dismiss it.