Introduction Conceptualizing democracy reveals that the term encompasses numerous ideas about the core meaning of democracy. It might solely refer to a formal, political model characterized by collective decision-making through elections and the separation of powers. On a normative level, the term democracy encompasses certain values and norms that citizens are living up to, for instance equality. Regarded from a social perspective, democracy gives structure to society and other entities such as firms, families and institutions by giving guidance for the interaction between societal actors. In order to fully understand and evaluate the theoretical term on the one hand and the practical functioning of a democratic system on the other hand, it is important to consider all the different spheres it touches upon. The interplay between people and politics, guided by norms and values, hereby represents the core of a democracy. In the form of different political arrangements such as representative or direct democracies and a multitude of formal processes, a democracy’s basic feature is the reciprocal interaction between society and state. By regulating the use of power, democracy structures the relationship between a multiplicity of institutions and their respective political and societal actors. Practically, both levels, political and social, have mutual expectations of how the relation between people and politics in a democracy should look like. Society demands the state to protect its rights and possessions while simultaneously guaranteeing its freedoms. By participating in political procedures such as elections, people exercise their freedom of speech and attempt to steer politics in a certain direction. Once citizens feel that their voices are no longer heard or that political efforts by the responsible authorities are tenuous, dissatisfaction with the political system and the government in office can emerge. At this point, the defining interplay between the social and the political sphere can be negatively affected due to a misfit between expectations on part of society and practice on part of the government. This misfit has found its expression in the rise of populist movements that can be observed in the European political landscape since the late 1970s. Growing societal resentment that reflects people’s discontent with contemporary politics challenges the functioning of democracies all across the continent. Illiberal voices stemming from oppositional groups and parties such as the French “Front National” and the German “Alternative für Deutschland” are increasingly pushing peoples’ attitudes further towards extremist positions and pretend to provide simple solutions to complex, geopolitical problems. Thinking about the present-day concept of democracy thus requires the inclusion of resentment as an inherent part of today’s political life. The theoretical interaction between state and society that is symptomatic for a democratic system, has to practically withstand the anti-democratic tendencies that in some cases, for instance in Poland and Hungary, even undermine fundamental state structures. As resentment recently emerged as an additional factor that has to be considered when talking about the concept of democracy, we should also assess the different effects that resentment can have on a democratic system. Framing societal resentment merely as a danger to democracy, neglects that democracy itself gives rise to this discontent. Resentment is thus coming from within the democratic system itself and can even have a strengthening impact on societal cohesion. Through challenging democratic structures, extremist and oppositional voices can increase the pressure on the political system and hence its responsiveness towards citizens’ demands. Critical debates and oppositional points of view within society and in the political arena incentivise to rethink the functioning of governments and to reconsider whether liberal values are sufficiently protected. The core feature of democracy, the interaction between social and political spheres, is thus still intact, but is expressed and acted out in a different manner. Confrontational approaches force politicians to contrast their actions with citizens’ demands and to evaluate whether both sides’ conceptions of democracy still coincide. Novel challenges, unanticipated crises and global political developments consequently create a need to redefine democracy, making it far more than a static and easily graspable term. The transformability of a democracy within a certain framework of values, norms and political responsiveness might thus be added to the concept’s core attributes. This variability and the multiple challenges that repeatedly put democracy’s social, political and normative spheres to a test makes it particularly interesting to study democratic systems in today’s complex environment. Based on the differentiated conceptualizations of democracy, this volume sheds light on the political and social system from different perspectives, aiming to better understand its complexity. In particular, the volume deals with the relation between democracy and resentment as it is one of the most shaping elements when trying to grasp the functioning or malfunctioning of present-day states. On the basis of country examples of, amongst others, the United States, Israel, Germany and Poland, the volume’s chapters scrutinize contemporary developments in these democracies and how the interplay between society and state is challenged in these specific cases. Next to providing an insight into the functioning of democracies in certain countries, the volume additionally deals with broader questions that are leading back to the fundamental ideas that a democratic state structure is based upon. Are the original, democratic notions still practicable in today’s society? How can a democratic system react flexibly to increasingly complex challenges without withdrawing citizens’ rights of involvement? Is there any form of “social capital” that can prevent political and societal groups from further fragmentation? Following the historic example of the French aristocrat Alexis de Toqueville who famously embarked on a journey to America to study the roots and the functioning of the American democracy in the 19th century, this volume observes and critically evaluates the concept of democracy in order to assess its strengths and flaws. We hope to offer academic input for a debate on a novel conceptualization of democracy, and to deliver potential solutions and approaches that can help to restore and strengthen the essential relation between society and state, aligning it to current and future challenges.