This chapter relates to the defenses against anxiety, and briefly describes the various types of defenses: Direct means of ego enhancement; Conciliatory forms of defense; Indirect and devious defenses; and Escape mechanisms. It devotes to an attempt to relate defense mechanisms, and relevant developmental considerations, to some of the formal diagnostic entities employed in clinical psychiatry. Obsessive-compulsive defenses against anxiety constitute one of the most common of all such defenses. The following three mental disorders to be discussed—somatization, hypochondriasis, and conversion—all have in common a form of overt physical symptom(s) as the manifest presenting symptomatology of this category of disorder. Dissociative fugue is very similar in adjustive mechanism and purpose to dissociative amnesia, but is more complex psychopathologically. The rigid dichotomy between malingering, on the one hand, and exhibiting and reporting only genuine symptoms, on the other, is highly idealized and simply doesn't exist in practice.