This chapter will discuss neuroscience and biotechnology-based biochemical and biological approaches that can be used for degrading human performance, or in other words, neuroweapons. As suggested in the introduction, neuroweapons are weapons that specifically target the brain or the central nervous system in order to affect the targeted person’s mental state, mental capacity and ultimately the person’s behaviour in a specific and predictable way. Such weapons fall broadly into the ‘nonlethal’ category, although it has to be stressed here that some of them could produce permanent and severe damage to people. In principle, there are four different approaches for creating weapons that can produce such affects: (1) drugs, or chemical and biochemical incapacitants, (2) bugs, or biological incapacitants (microorganisms and biological toxins), (3) waves, or directed energy weapons and (4) bytes, or cyber and informational weapons (the latter two types will be discussed in the next chapter). These weapons can have mild or merely incapacitating effects, inbetween behavioural effects (e.g. by inducing emotions) or may have extreme effects (mental coercion) (Sirén, 2013, 86). Publicly acknowledged are only NLW with mild or incapacitating effects. However, there are many reasons to believe that more specific behavioural effects using biochemical or biological agents may be possible in the future, as will be shown below. It will be argued that the use of chemical and biochemical agents for affecting behaviour is currently the most promising approach for a neuroweapon and there is a good amount of scientific literature that indicates a lot of potential in this area (Pearson et al., 2007). Currently less understood are the biological and genetic roots of behaviour. Nevertheless, new bioweapons could be engineered to have some targeted behavioural effects (Moreno, 2012: 200-201).