I enjoyed chapter 15 the most; it is a new contribution written specifically for this book. The notion of self-medication is one of the most intuitively appealing theories in the field of addictions. The more closely a drug matches what is missing in the person or more effectively treats a disease, the more powerful and reinforcing. This hypothesis is consistent with biological theories of addiction liability as well as the theory of drug use as reinforcement or pleasure. A person with an alcoholic biological parent finds that alcohol is the key to an internal lock, that it is more like heroin than alcohol. Khantzian reiterates that drugs of abuse relieve psychological suffering and that a person’s preference for a particular drug involves some sort of psychopharmacological choice or specificity. Patients experiment with various classes of drugs and discover that one is better because it ameliorates, heightens, or relieves affect states that are problematic or painful. With his patients, Khantzian explores suffering, character, and self-medication and develops treatment based on the patient’s inner-life characteristic defenses. Through the therapeutic alliance, patients develop an understanding of how their suffering, defenses, avoidances, and separation relate to their drug use.