International Humanitarian Law (IHL) regulates the conduct of war, and draws from a variety of sources, but relies primarily upon instruments of law such as the Geneva Conventions and the Hague Conventions. The more recent of these instruments, the fourth Geneva Convention, was devised in 1949. Needless to say, rapid technological advances render these legal instruments a crude fit for modern technologies of war. Irrespective of this, cyber weapons are becoming increasingly popular, with the increasing investment of states in their military capacity for cyber warfare. This presents some significant challenges for IHL, but it is the only body of law that regulates and constrains armed conflict. The policy and law regulating cyber warfare is certainly going to be updated and modified by state governments and international organisations, and technical consultation and guidance is essential in order for this process to be effective. The most promising development in this respect originates from the Tallinn Manual, which comprises detailed research applying IHL to cyber warfare, drafted by IHL academics and technical experts. However, whilst a well regarded and influential manual, it has a number of issues: it is not legally binding, applies only the current outdated laws to cyber warfare; does not propose new laws; and (perhaps most saliently) the technical expertise received in the drafting of it consists of two technical advisors from NATO. This last point raises some significant questions as to the impartiality and function of the document, and whose interests the document serves, in addition to a dearth of technical opinion and a total lack of consultation with the internet governance community.