What have we learned about the psychological effects of the COVID-19 pandemic? Although we have largely returned to a normal mode of life, with most pandemic-related protective measures having been lifted, research on the psychological effects of the COVID-19 pandemic is still ongoing. This volume takes the opportunity to examine research from different psychological perspectives, including child and adolescent, educational, organizational, differential, biological, as well as social psychology. Eight chapters focus on aspects of mental health and well-being in particular affected target groups, including adolescents and students, teachers, crisis managers, and people with low socioeconomic status. The range of methods used in the original research is multi-faceted and includes, in addition to subjective surveys, ambulatory assessment, psychophysiological methods of fear conditioning, and genetic research approaches. Many of the contributions are based on well-characterized longitudinal cohorts. This volume demonstrates the diversity and methodological quality of the research that has been conducted under difficult pandemic conditions. Researchers, practitioners, and students will find the results helpful in developing evidence-based recommendations for at-risk groups to deal with similar future crises.