\u27Summer drenching\u27 has been a highly successful strategy for controlling sheep worms in Western Australia\u27s winter rainfall regions for many years. Drenching to remove worm burdens in summer, when the risk of reinfection by worm larvae is low, is an efficient basis to year-round worm control. The Department of Agriculture recently altered its recommendations for the timing of summer drenches to take account of new findings regarding the survival of worm larvae over summer. It now recommends that sheep farmers give the first summer drench when the pasture is beginning to dry off, in spring in most locations. Experiments atMt Barker Research Station have confirmed the effectiveness of the new recommendations, buthaveshown the need for additional control measures for barbers pole worm