ABSTRACT. The present article summarizes themy and data about symptomutology, epid.emio&y, and etiology of specijii phobias. Additionally, the cognitive mechanisms involved in specific phobias are briefly discussed. By and Icrrg, the general pattern behind tk development of specific phobias can be summarized as follows. Specijk fears are highly preualent among young children. In most children, these fears r@esent transitory phenomma. Howevq in a small sub grvup of children, speczfu: fears become chronic due to classical conditioning, modelling, and/or negative infMmation transmission. Once a specjk phobia bus okveluped, it may be maintained by cognitive biases (i.e., attentional bias, covariation bias, and reasoning bias). Though specif ic phobias form a heterogeneous class of disomks, this pattern appears to be a good approximation. Neverth.ebzss, several questions remain. For example, there is no ready explanation for the fact that specijc phobias are mo7e often diagnosed in women than in mm. Similarly, it is not clear to what extent the nonrandom distribution of phobias can be interp-ted in terms of cultural factors. Resolving these issues is not only important in its own right, but may have considerable kristic value fm our unokrstanding of other anxiety disorti.SPECIFIC (formerly "simple," "monosymptomatic," or "focal") phobias are irrational and persistent fears of certain objects or animals. Whereas the concept of "specific phobia" is relatively recent, the condition to which it refers is not (Errera, 1962). For example, Hippocrates described a man displaying an irrational fear of bridges. Likewise, detailed discussions of phobic symptoms can be found in the work of 17th and 18th century authors such as Descartes, Le Camus, and Sauvages. Although descriptions of phobic behavior have remained remarkably consistent throughout history, theories purporting to explain this behavior have changed dramatically. In early medical texts, speculations about eye muscle dysfunction, vascular abnormalities, or mysterious underground water streams were not uncommon (Errera, 1962). During the past decades, our understanding of the origins of specific phobias Correspondence should be addressed to Harald Merckelbach,