In view of the promise attached to the recent attempts to integrate learning and personality theory (Eysenck, 1957), and the suggestion that drug addiction might be a learned response, it would appear profitable to consider the relevance of this integration to a better understanding of addiction, a suggestion reinforced by two recent papers by Partridge (1959a, b). On the basis of a clinical survey of addiction he came to the conclusion that the extent and severity of addiction was dependent on “… the extent to which the particular personality can tolerate them (i.e. the symptoms, such as anxiety, which would arise without the drug) … patients with a low tolerance of discomforts and frustrations are those more likely to be addicts, just as they are more likely to turn to drugs in the first place … the development of addiction, in fact, depends much on the personality … the form of addiction depends more on the circumstances and opportunities with which the particular personality has been confronted.” Such considerations and conclusions can be conceptualized within and predicted from the theoretical framework to be proposed later in the present review.