‘Recreational drugs’ explores the origins, mechanisms, and criminalization of many widely used drugs. Many recreational drugs are legal including alcohol, tobacco, and caffeine, which are all widely available. Other drugs are controlled by law. Cannabis is the most commonly used illegal drug, but some people advocate its use in pain relief. Likewise, amphetamines have been used as decongestants and in treating ADHD, but its criminalization led to the development of designer drugs such as ecstasy. Heroin and cocaine are considered as harder drugs that carry many more risks to users and society. Many Western countries have strict drug laws, but there are moves in some countries to legalize or decriminalize cannabis.