Before you can talk about drug rehabilitation, you have to consider what addiction is. According to the dictionary, addiction is the fact or condition of being addicted to a particular substance, thing or activity. This of course forces the dictionary reader to look up "addict" which is defined as a person who is addicted to a particular substance (breaking the old grammar school rule about using a word to define itself). Ironically, somehow the definition manages to cause a cycle similar to the actual fact of addiction. But it has to stop somewhere. Addiction is an uncontrolled proclivity for a certain drug. Most drugs cause physical as well as psychological addictions, so any type of rehabilitation must address both physical and psychological factors. That uncontrolled proclivity in an addict can be likened to thirst. You know when you are thirsty. You are not only satisfying the need for water; you are also preventing the discomfort of being without water. This is the type of crisis that the addict faces--not only are they slave to the need; they are also enslaved to preventing the pain of being without.