Fear and anxiety are basic emotions of humans as well as of all higher animals. Their evolutionary importance and relevance for the individual are due to their central role in preparing for flight and fight and thus their contribution to survival. They are integral elements of the human condition and have been topics of philosophical essays like the one by Spinoza as well as works of art like the paintings by Munch and Klee. However, excessive fear and anxiety in their pathological forms of anxiety disorders are not only associated with extreme emotional stress for the affected individuals, but also utterly dysfunctional by making a normal life for them impossible.

Anxiety disorders are thus held to belong to the most common, disabling and persistent mental disorders. Lifetime prevalence estimates go as far as 20% creating one of the largest burdens of morbidity in individuals of the reproductive age (WHO and Wonca 2008). There is an urgent need both for a better understanding of the aetiology and development of the different anxiety disorders as a basis for better treatments. Traditionally though, research efforts of the scientific community have focused on neurodegenerative, psychotic, affective and dependence disorders. This in spite of the fact that anxiety disorders occur early in life and are quite often the precursor of both affective and dependence disorders further increasing their contribution to individual suffering and health costs.

But yet, there is hope, not only in terms of better recognition of anxiety disorders by health professionals, earlier treatment of affected persons and increasing acceptance in society, but also due to basic and clinical research of the recent decade. The 9th annual meeting of the Society of Anxiety Research at the Psychiatric Department of the University of Wuerzburg in the autumn of 2007 mirrored the scientific efforts of German researchers on a wide spectrum of anxiety-related topics. Presentations covered a wide range from animal models and genetics of anxiety disorders over physiological markers and functional imaging to novel treatment strategies. This special issue contains some of the most important contributions at this meeting complemented by other recent work from leading German groups including reviews on important fields of research on anxiety disorders.

Several articles deal with potential psychosocial as well as genetic causes of anxiety disorders. A better understanding of these underlying factors obviously is essential for the development of prevention strategies, always the best therapy if available. Other studies focus on animal models and intermediate phenotypes using biological serum markers, electrophysiological markers and functional MRI techniques. As opposed to other mental disorders, there are valid rodent animal models for defined behavioural aspects of fear. One of their strengths is that they allow to study gene–environment interactions and the development of fear behaviour over the life-span and thus the developmental aspects of fear. They will complement intermediate phenotype approaches by contributing to a better understanding of the neurobiology of anxiety disorders which is necessary for the development of novel therapeutic approaches. As the study of some aspects of anxiety such as the emotional experience and cognitive processes cannot be readily performed in rodents, basic human studies on fear conditioning and extinction are essential for a better understanding of the specifically human aspects of fear and anxiety. Finally, all therapeutic concepts developed by basic research have to prove their relevance in the clinical situation. Reviews provide an overview on the state of the art of the multimodal treatment of anxiety disorders and two pilot studies report novel approaches to the prevention and therapy of anxiety disorders.

This special issue on Anxiety with its many contributions clearly demonstrates that research in the field of anxiety disorders is rapidly developing. Novel initiatives such as the BMBF psychotherapy network “Improving the treatment of Panic Disorder—From a better understanding of Fear Circuit Mechanisms to more Effective Psychological Treatment and Routine Care” and the transregio SFB TRR59 “Fear, Anxiety and Anxiety Disorders” provide substantial reason for hope—hope for an accelerated advance in research to bring relief for those who fear.