Sleeping under an insecticide-treated net protects the sleeper from mosquito bites and is highly effective means of reducing the risk of malaria. Recent studies in The Gambia and Kenya have shown that untreated bednets in good condition can also protect against malaria (51% protection against parasitaemia, 95% CIs 34-64%). However, most children in rural Gambia sleep under untreated nets in poor condition, often with a few holes, and do not close their nets properly at night. These children remain exposed to mosquito bites and the risk of malaria.