This chapter will consist of a discussion of some theoretical reasons for directing pictorial image-making to psychotherapeutic ends; in effect to try to supply a number of justifications for such an apparently specialized technique. If a procedure is to be thought of as therapeutic then there is an ethical requirement that its efficacy can be clearly demonstrated and the reasons for this pointed to. I do not think it unfair to claim that the literature that exists at present is less convincing than it might be in this respect. If art therapy is conceived of as a psychotherapy however, that is using the term psychotherapy generically to embrace the class of psychological therapies as a whole, then the idea of efficacy and the reasons behind it may be more complex, subtle, and extended than has been usually imagined. Indeed psychotherapy is beset by many of the same problems of evaluation as bear upon art therapy. It has been said of psychoanalysis, for example, that it is a speculative explanation of human behaviour offered in advance of the empirical evidence that might justify it. Some of these problems of justification may, however, arise from false conceptions concerning scientific approaches to human action and experience. The view is increasingly gaining ground that appropriate methodologies in the social sciences might have no recourse but to be rooted in the real life situations which are in fact being examined, rather than in artificially contrived experimental conditions (Harré and Secord 1975, Glymour 1982). This is certainly true of traditional sciences such as astronomy and modern ones such as ethology, both of which investigate phenomena in their naturally occurring context. Other disciplines concerned with knowledge of human action, for example anthropology and linguistics, as well as many of the classical humanities like history, law, criticism, and aesthetics, depend upon methods naturally fitted to the phenomena with which they are occupied.