private void menuZones_Click(object sender, EventArgs e) { //Create a new instance of the Zones editor frmZones zones = new frmZones(); //Show it as a dialog. This prevents other editors from starting at the same time. //Ensures that the static Editor Type will only be accessed by one editor at a time. zones.ShowDialog(); //While the editor is visible, just keep the App responsive. while (zones.Visible) { Application.DoEvents(); } //Null the reference we have. zones = null; }