This book provides a systematic overview of the prevalence, causes, and stability of left-wing and right-wing extremist attitudes in Germany between 1994 and 2017. It shows that there are many similarities between left-wing and right-wing extremists, both in terms of their ideologies and their individual experiences. Overall, these causes can be traced back to three factors: unmet individual needs (e.g., deprivation or disenchantment with politics),...