Although everybody had and will experience anxiety, its intensity, frequency and characteristics may vary from what can be considered as "normal" to pathological. The development of benzodiazepine as anxiolytics has been a major step firstly in therapeutics and secondly in the understanding of the associated biological mechanisms. Recently, new drugs without secondary effects of benzodiazepines have been developed. The purpose of the book was to take stock of the present knowledge: clinical aspects of pathological anxiety, neurobiological mechanisms associated with stress and anxiety, molecular targets of potent anxiolytic drugs, new issues and directions.