A few years ago, consumer products giant Sara Lee (SLE) started seeing knockoffs of its biggest seller in Africa, Kiwi shoe polish. The company fought back by updating the Kiwi label, but the counterfeiters quickly matched it. So Sara Lee introduced new packaging sizes. A half-year later the fakes were showing up in the new sizes. Then the company changed the mold to give the Kiwi tins a deeper rim, but counterfeiters soon had nearly identical ones on the market. "Every time we change something, their lead time gets shorter and shorter," says Joab Ouma, who at the time was Sara Lee's marketing director for East Africa and now works independently as the company's distributor in Uganda. "First it was six months, and now it's as little as six weeks."