Comprehensive harm reduction strategies should address all 7 components of risk in drug-taking behaviour. These include: Contexts of use (eg. nightclubs, public places), Amounts used (per session and across time), Methods of use (notably injecting and inhaling), Patterns of use (notably frequency of use), Mixtures of drugs (per session and across time), Access to drugs (eg. how drug use is funded), and drug Products (purity, adulterants).