This open access book explores the macro-social influences on loneliness in later life, emphasizing how societal structures, cultural contexts, and broader social transformations shape the experience of loneliness. Dedicated to the social construction of loneliness and the notable heterogeneity in its prevalence across European countries, this volume brings together a distinguished selection of experts who share their latest insights on meso- and macro-level influences, cultural and structural theories, and the impact of digitalization, climate change, and societal crises. Divided into five parts, the book addresses key aspects of this complex issue. The first part introduces the central themes, outlining the relevance of loneliness as a societal concern and discussing the limitations of existing research, which predominantly focuses on individual-level factors. It highlights the need for a multi-level approach that incorporates micro, meso, and macro perspectives to fully understand the contextual influences on loneliness. The second part delves into theoretical perspectives, offering a comprehensive framework for understanding loneliness at different levels. It examines the interplay between individual, relational, and societal factors while also exploring cultural and social exclusion perspectives that shed light on how loneliness manifests across different contexts. The third part presents empirical evidence, focusing on variations in loneliness across different social groups and regions in Europe. It synthesizes research on micro- and meso-level determinants while also providing a review of macro-level influences. This part highlights the role of welfare regimes, demographic trends, and broader societal conditions in shaping the prevalence and experience of loneliness. The fourth part explores recent societal developments that may influence loneliness, including digitalization, migration, climate change, and societal crises. These emerging topics illustrate how macro-level transformations can either alleviate or exacerbate loneliness, depending on how they interact with existing social structures and individual circumstances. The final part discusses methodological advancements and policy implications. It introduces an innovative approach to analyzing macro-social influences on loneliness and revisits the ‘loneliness paradox’ in light of new findings. The book concludes with policy recommendations and future research directions, emphasizing the need for a holistic approach that integrates individual, relational, and societal dimensions to develop more effective interventions against loneliness. In sum, by adopting a macro-social lens, this book contributes to a deeper understanding of the societal, cultural, and policy-related determinants of loneliness. It offers a foundation for evidence-based interventions that go beyond individual-level solutions, recognizing loneliness as a socially embedded phenomenon shaped by broader societal forces. It is our hope and expectation that the book and its content will fundamentally change our understanding of loneliness and strategies to combat it.