Counter-insurgency is fashionable again: more has been written on it in the last four years than in the last four decades. This is heartening for those who were in the wilderness during the years when Western governments regarded counter-insurgency as a distraction, of interest only to historians. So it is no surprise that some have urged the re-discovery of classical, 'proven' counter-insurgency methods. But today's insurgencies differ significantly - at the level of policy, strategy, operational art and tactical technique - from those of earlier eras. An enormous amount of classical counter-insurgency remains relevant. Indeed, counter-insurgency provides the 'best fit' framework for strategic problems in the 'war on terror'. But much is new in counter-insurgency redux, possibly requiring fundamental re-appraisals of conventional wisdom.