Hitherto 'less-lethal' weapons, in contrast to classical firearms and other highly destructive weapons, have literally slipped under the radar of public international law. This book is the first monograph addressing and analysing all international legal regimes applicable to less-lethal weapons, ranging from arms control treaties, international humanitarian, criminal and human rights law. In doing so the different scenarios in which less-lethal weapons come to use will be taken into account, such as law enforcement, armed conflict and law enforcement scenarios during armed conflict. The relationships between the different legal regimes will be elaborated thoroughly with a view to examining how international law responds to less-lethal weapons. The final chapter provides guidelines as well as recommendations on appropriate use and regulation of less-lethal weapons, where the different scenarios of application, such as in armed conflict and law enforcement, will be given due account.