Abstract Anxiety disorder is a psychological problem in individuals who are known to worry too much and have fears that are unrealistic. These disorders have been known to cause diverse psychological and physical damage. The classifications of anxiety disorder include the phobias, the generalized anxiety disorder, panic disorder, agoraphobia, social anxiety disorder, obsessive-compulsive disorder, separation anxiety and post-traumatic stress disorder. Each of these disorders has different symptoms and treatment procedures.Research indicates that diagnosis of the disorders may be difficult since the symptoms overlap with other common ailments. However, various treatment interventions exist. The use of cognitive-behavioural therapy such as the use of talk therapy is very effective. The therapist tries to unearth the causes of such anxieties and fears and helps the patient realize that it was exaggerated and unrealistic. The use of medication such as the SSRIs is also effective. However, some have adverse side effects. Research questions I. What is the diagnosis of anxiety disorder? II. What treatment interventions are available for anxiety disorder? Introduction The Diagnostic and Statistical Manual of Mental Disorders (DSM) provides information about anxiety disorder as it relates to the course, Abnormal Psychology (Butcher, Mineria, & Hooley, 2007). It has been defined as the various forms of the psychiatric disorders that involve the repetitive focus on symptoms of distress, worrying, being uneasy and worrying about what will happen in the future. This fear about what the future holds may be based on facts or imaginary things. There are other medical conditions that may imitate and be misdiagnosed as anxiety disorder. One of them includes hyperthyroidism. This disorder is unhealthy to any human since it may negatively affect the psychological and physical health of the individual. Anxiety disorder is like a disease that requires proper diagnosis and prompt treatment. There are several psychosocial causes of this disorder. Some causes are genetic by nature. The persons who have been diagnosed with the disorder may be classified into two groups. The first classification is the group of individuals who are experiencing continuous symptoms. The other classification consists of individuals whose symptoms only seem to occur episodically. According to research, there are several types of anxiety disorders. Research also indicates that at least one of the disorders affects about 20% of Americans and approximately 15% of Europeans (Kessler, Chiu, Demler, Merikangas, & Walters, 2005). When one is said to be anxious, the individual may be going through one or more of the four experiences. These include dissociative anxiety, tension, apprehension or certain physical signs. Anxiety disorder may be divided into three broad categories. They include panic, phobic and generalized anxiety disorders. All of these disorders have their different symptoms and each requires a different intervention (Gelder, Mayou, & Geddes, 2005). The individual suffering from an anxiety disorder experiences diverse emotions of different capacities. Some may experience simple nervousness (Barker, 2003). However, others may have bouts of terror. This paper will examine the Axis 1 diagnosis of Anxiety Disorder and assess some of the