This chapter introduces the key issues related to terrorism in Russia. First, it considers the emergence of Islamist terrorism in the Northern Caucasus as the dominant aspect of terrorism in Russia in the context of the end of the Soviet Union, the troubled decade of the 1990s and particularly the two Chechen Wars. It also highlights the further developments during the post-9/11 years and the more recent linkages to ISIS and Russian foreign fighters in Syria. The chapter then moves on to explain the impact of terrorism in and from the Northern Caucasus on the Russian state and society. This highlights how the errors and failures of earlier dealings with Islamist terrorists influenced the development of Russia’s counterterrorism approach. The third section outlines these responses of the Russian state and society. It also includes a brief discussion of the above-mentioned international cooperation on anti-terror measures. The fourth section introduces the literature on radicalization as a key current research agenda in the field. Drawing on Russian authors and sources, this section seeks to present the state of the art of research on the radicalization, motivations and recruitment of Russian jihadists.