Psychiatrist Zinberg, of Harvard Medical School, is the co-author of a previous responsible argument for controlled drug use, Drugs and the Public (1972), and the editor of a thematically-related anthology, Alternate States of Consciousness (1977). Here, he also follows in the train of George Vaillant and others who suggest that, under the right circumstances, social drinking may be safe even for former alcoholics. Non-punitive British treatment of heroin addicts presented Zinberg with a population of long-term drug users who are not now addicts by any definition; he went on to conduct a five-year study of 153 drug users in the Boston area--in order to establish what factors must be present in the drug, in the ""set"" (personality of the user), and in the setting for long-term controlled use to occur. Most of the successful subjects, we learn, were introduced to drugs by friends or relatives who used them in a similar, controlled way. Self-imposed rules--like restricting drug use to weekends, or to the company of certain friends--and other limiting circumstances contribute to a control-setting. Finally, Zinberg presents a psychodynamic personality theory that allows intoxicant use as a normal act--by seeing human interest in consciousness-change ""as an integral function of the ego, part of its capacity to develop and change thresholds for discharge. . . of primitive affects and fantasies."" His chief argument, however, is that the drug, the user's personality, and the social setting must all be considered in deciding whether a drug is being used or abused. This, of course, challenges the current overwhelming view that use of certain drugs is always abuse. There are lingering, internal difficulties. Isn't it significant that people are willing to take the purely physical risk of shooting unknown, adulterated substances into their bloodstream?) But Zinberg has nonetheless contributed to the growing body of evidence that currently supports this case.