It is reassuring that a number of leading Japanese manufacturers have just issued positive trading results. The growth figures come as good news in the wake of the recent devastating earthquake, tsunami and nuclear catastrophe. But there's no doubt that the disasters will impact on later results, even though most of the big players escaped direct impacts in the natural disasters. The diverse supply chains have been affected and will no doubt continue to hamper any return to full production. It all goes to show how one never knows what challenges loom. Until very recently, the primary concern was falling demand. Now, the issue is one of supply. What next?