Cross-cultural research methods, as discussed by van de Vijver and Tanaka-Matsumi, are essential in abnormal and clinical psychology due to increasing global interest in cultural differences and acculturation. The authors highlight the need to adapt research and theories to account for cross-cultural variation, particularly in understanding the relationship between cultural factors and psychopathology. They emphasize that clinical syndromes may vary across cultures, and that assessment procedures and therapies must be adapted for multicultural populations. The chapter explores the universality and cultural specificity of clinical syndromes, including the concept of culture-bound syndromes, such as Amok and Ataque de Nervios, which are specific to certain cultures. The authors also discuss the challenges of cross-cultural comparisons, including bias and equivalence, and the importance of considering acculturation in mental health. They propose a framework for classifying cross-cultural problems and ways to avoid them, as well as the role of acculturation in mental health. The discussion includes the impact of acculturation on psychological health, the stress associated with acculturation, and the importance of cultural accommodation in assessment and psychotherapy. The authors conclude that cross-cultural research is crucial for understanding and addressing mental health issues in diverse populations, and that culturally informed approaches are necessary for effective treatment and assessment.Cross-cultural research methods, as discussed by van de Vijver and Tanaka-Matsumi, are essential in abnormal and clinical psychology due to increasing global interest in cultural differences and acculturation. The authors highlight the need to adapt research and theories to account for cross-cultural variation, particularly in understanding the relationship between cultural factors and psychopathology. They emphasize that clinical syndromes may vary across cultures, and that assessment procedures and therapies must be adapted for multicultural populations. The chapter explores the universality and cultural specificity of clinical syndromes, including the concept of culture-bound syndromes, such as Amok and Ataque de Nervios, which are specific to certain cultures. The authors also discuss the challenges of cross-cultural comparisons, including bias and equivalence, and the importance of considering acculturation in mental health. They propose a framework for classifying cross-cultural problems and ways to avoid them, as well as the role of acculturation in mental health. The discussion includes the impact of acculturation on psychological health, the stress associated with acculturation, and the importance of cultural accommodation in assessment and psychotherapy. The authors conclude that cross-cultural research is crucial for understanding and addressing mental health issues in diverse populations, and that culturally informed approaches are necessary for effective treatment and assessment.