His research focuses on three main area of interest. First, the cultural adaptation process. Within this area of study he has explored adaptation in 15 nations. Within these studies he has shown through qualitative and quantitative analyses that current models of adaptation do not adequately describe: the fusion of identities that occur during adaptation, and the influence/resistance of the host culture. Second, and closely related to cultural adaptation, is his work into integrated threat theory. In these studies Croucher has shown how many dominant cultural groups in Europe, North America, and Asia fear immigrant and minority communities. These fears (prejudice) lead to less acceptance of adaptation overtures from the minority groups. Third, he studies the relationships between communicative behaviors/traits and religious identification and religiosity. In this line of work he has found religion (identity and religiosity) to have a significant effect on a variety of traits/behaviors.
Croucher has published 4 books and more than 50 articles in journals such as: Communication Monographs, Journal of International and Intercultural Communication, Management Communication Quarterly, Communication Studies, International Journal of Conflict Management, and Journal of Intercultural Communication Research.
Croucher is active in various professional associations and has served in a variety of capacities: Vice-Chair of the Intercultural Division of the International Communication Association, editor of the Journal of Intercultural Communication Research and Speaker & Gavel, and World Communication Association Vice President for Europe. He has also served on the editorial board of numerous journals: Communication Studies, Journal of International and Intercultural Communication, International Journal of Conflict Management, Mass Communication and Society, and the Western Journal of Communication.