This book forms an introduction to the emerging discipline of "psychology of migration", which is an interdisciplinary field of reflection and research, joining together diverse subfields of psychology with anthropological, sociological, demographic and historical inquiry on migration processes. The introductory chapter marks the borders of this borderline discipline, defines important notions and the subject of inquiry, and presents its main research themes together with prospective paths for the discipline's development. The second chapter presents research methods applied in psychology of migration. Acculturation processes and their psychological analysis as well an impact on the mental health of migrants are the main topics of interest in the third chapter. The last chapter covers issues of mutual relations between religion and migration. Conclusive remarks on contemporary psychology of migration facing cultural and religious diversity in COVID-19 pandemic times are outlined, pointing at challenges the discipline will surely meet in the future.