International students who travel overseas in pursuit of education face a myriad of challenges. These challenges range from managing intercultural communication interactions, dealing with cultural differences, and adapting to new environments. As part of cross-cultural transition, sojourners often bring with them preconceived notions and expectations of what they will experience. However, under-met expectations can exert stress and impede successful adaptation. This thesis examines the role of pre-arrival expectations and the impact of expectancy violation on cross-cultural adaptation over time among international students in Australia. The research employs a longitudinal panel study with three surveys conducted over 13 months involving newly commencing international students at The University of Queensland. The theoretical framework guiding this thesis incorporates cross-cultural psychology and cross-cultural communication theories: the theory of acculturation, integrated theory of communication and cross-cultural adaptation, and expectancy violation and interaction adaptation theories. The theory of acculturation establishes the field of research on cross-cultural transition, and is particularly crucial to the understanding of the process of acculturation over time. The integrated theory of communication and cross-cultural transition incorporates communicative aspects of cross-cultural adaptation within the acculturation process. Expectancy violation theory provides an understanding of the role of expectations and the impact that expectancy violations have on cross-cultural adaptation. Finally, interaction adaptation theory informs on the intercultural communication behaviour and coping strategies that sojourners engage in when expectations are violated. The first study establishes international students' pre-arrival expectations of life in the host country relating to a number of expectation dimensions (such as expected cultural distance, sociocultural difficulty, discrimination, and acculturation orientations). The second study investigates the postarrival experience of international students, explores the extent to which expectations are met or violated post-arrival, and examines the impact of pre-arrival expectations and expectancy violations on six-month post-arrival psychological and sociocultural adaptation. Finally, the third study investigates the impact of pre-arrival expectations and expectancy violations on 12-month postarrival adaptation, as well as the patterns of change that occur over time, in the different components of cross-cultural adaptation. The results from this research reveal that international students experienced violations (both positively and negatively) as well as non-violations to their pre-arrival expectations once they arrived in the host country. Actual experience, more than pre-arrival expectations, was related to viii