There is a time-honoured tradition in academia of writing a liber amicorum for a senior at the end of a typically successful career in university. But, as we know from ethnography, even rituals with a seemingly similar purpose come with much cultural variation. The idea of a combination of a universal theme and local variations is applicable to this book in a double sense.

First, it explains why the book has been written. Ype Poortinga is no longer Professor of Cross-Cultural Psychology at Tilburg University, the Netherlands, but has become an emeritus professor. This book is a liber amicorum dedicated to Ype as the founding (and still active) father of cross-cultural psychology in Tilburg and a key international player in the field. Yet, we deviate from the implicit recipe of the liber amicorum. This variation is mainly inspired by Ype's preferences. We think that a book with an up-to-date overview of modern theories and models in cross-cultural psychology will give him much more pleasure than a selection of chapters with anecdotes from his colourful past, in however lively a manner these are described. History is important in the book, not as anecdotes, but as references to the state of cross-cultural psychology forty years ago and to its current state. We take stock of cross-cultural psychology of the last forty years, which roughly spans Ype's professional career as well as the rise of empirical cross-cultural psychology.