The book "Intercultural Adaptation Research," co-authored by five scholars including Hou Junxia, systematically organizes the theoretical frameworks and methodological systems in the field of intercultural adaptation research over the past century, providing an invaluable "academic map" for the discipline. Grounded in the historical foundation of intercultural adaptation studies, the book employs exhaustive literature review and a critical perspective to systematically outline the research themes, dimensions, focuses, core concepts, key theories, and research methods across different historical stages, delineating the overall evolutionary trajectory of intercultural adaptation research. The scope of the review encompasses relevant domestic and international monographs and journal articles, covering representative scholars, major schools of thought, classic theories, and cutting-edge developments, thereby revealing the intrinsic knowledge structure and academic logic of the field. It stands as a comprehensive and practical academic reference. Written in accessible language, the book reduces the cognitive load for novice scholars while maintaining scientific rigor and readability. Based on historical analysis, the most original theoretical contribution of the book lies in proposing the "theoretical perspective of intercultural adaptation space adjustment." The core of this perspective is the authors' new working definition of "intercultural adaptation," defined as "the process of cognitive, behavioral, emotional, and identity changes experienced by individuals and groups in motion across different cultural experiences, constituting a complex dynamic system shaped by multiple influencing factors—including macro-level national history, culture, social structures, and policy systems; meso-level community institutional environments and family cultural capital; and micro-level individual personality, attitudes, and agency. This system simultaneously exerts a reciprocal influence on the environment, constructing the space for intercultural adaptation adjustment." The core value of this definition lies in its integration. It builds upon Berry's "dual-process" model, incorporates Ward's psychological-behavioral-cognitive dimensions, and integrates a micro-meso-macro multi-level ecosystem perspective. The concept of "adjustment space" transforms the adaptation process from passive endurance to active construction, revealing the complex nature of intercultural contact, which changes all individuals involved and the environment itself. This goes beyond traditional static, unidirectional frameworks of understanding intercultural adaptation, aligning more closely with its ongoing negotiation and mutual shaping, providing a powerful theoretical tool for understanding cultural hybridization and identity negotiation in the era of globalization. The book elaborates on the evolution and reconstruction of the core terminology "intercultural adaptation." Intercultural adaptation research originated in the late 19th and early 20th centuries. McGee and Simmons distinguished "intercultural adaptation" from "assimilation" from anthropological and sociological perspectives, respectively. While groundbreaking, their work implied linear evolutionary tendencies and cultural hierarchies. Scholars like Redfield, in the "Memorandum on Intercultural Adaptation Research," explicitly defined intercultural adaptation as changes in cultural patterns of one or both groups resulting from sustained contact between different cultural groups, emphasizing the bidirectional nature of cultural interaction and establishing a relatively egalitarian theoretical tone. However, this research remained confined to the group level and did not extend to the individual level. Graves explicitly proposed a dual analytical framework of group-level cultural change and individual-level psychological adaptation, truly expanding the research scope of intercultural adaptation. Since the 1990s, Berry gradually developed the influential acculturation strategies model and explicitly defined intercultural adaptation as the dual process of psychological and sociocultural changes occurring after contact between two or more cultural groups and their members. This definition further addressed previous neglect of individual adaptation mechanisms and highlighted the dynamics and equality in intercultural interaction. Ward and colleagues distinguished psychological adaptation from sociocultural adaptation across affective, behavioral, and cognitive dimensions, refining the understanding of adaptation mechanisms. Within the Chinese academic context, scholars further conceptualized distinctions between "enculturation" and "acculturation," deepening theoretical understanding of the intercultural adaptation process. The book clearly presents the iteration and evolution of classic theories in intercultural adaptation research. Early theories, such as culture shock theory, viewed psychological discomfort in intercultural adaptation from an anthropological perspective as a kind of "disease" and initially proposed a four-stage adaptation model, laying the foundation for stage-based research. Simultaneously, the U-curve hypothesis introduced a temporal dimension from a social psychological perspective, emphasizing adaptation as a dynamic, nonlinear process, further solidifying the stage-division research paradigm. The W-curve hypothesis proposed by the Gullahorns extended the U-curve model by incorporating the re-adaptation process upon returning home, reflecting the complexity of the entire intercultural adaptation journey. Transformation theory reconceptualized "culture shock" as "distress caused by transition," though it still carried the "disease metaphor" and overlooked opportunities in abrupt environmental changes and potential personal growth, providing an important transition for theoretical development. Subsequently, individual development theory achieved a significant breakthrough, with scholars proposing that "transitional experiences" could serve as opportunities for higher-level personality development and self-growth, thereby shifting intercultural adaptation from a negative disease narrative to a positive transformation perspective and expanding theoretical connotations. In the stage of identity theory, research further deepened and became critical. Japanese scholar Yoshikawa's "double-swing model" emphasizes the dynamic negotiation between self and others in the "in-between" space.