The Casuals have the "Perma Pleats" sewn in, so they don't need to be ironed, but the Semi Trads do not. They need a "touch up" after washings to make them lay flat and perfect. The pleats are still VERY visible after washing them, they justtend to get a bit "puffy" out of the wash. You CAN wear them straight out of the wash for the "lived in" type of look or iron it for the crisp clean look.