Although high risk and low risk profile for thrombo-embolic events have been extensively and intensively investigated in multi-centre trials and described in detail in atrial fibrillation guidelines, the management of those at otherwise intermediate risk is still a 'no-one's zone'. Individual risk profile is mandatory to identify those who will benefit of anti-coagulation therapy and large-scale clinical trials are still awaited to define efficacy and efficiency profile in intermediate-risk group.