Rachel Marshall from the Cochrane Editorial Unit introduces the September 2011 round-up of what's new on The Cochrane Library. This month's round-up features Cochrane Reviews on fortification of foods with micronutrients for young children, antiemetics for vomiting in acute gastroenteritis, ways to help people to remember to take their tablets, repairing water-damaged buildings for preventing chest conditions, and oral analgesics for acute postoperative pain.