Scholarly reflection on kindness raises a variety of issues and perspectives. In order to consider the impact of kindness on various aspects of human existence, it is first necessary to give it a concrete meaning. This seemingly simple task turns out to be quite challenging. The prevailing definitional chaos in the literature, the lack of consensus on basic terminological assumptions, indicates a deficit in the theoretical understanding of the concept of kindness and, perhaps more importantly, poses a problem when attempting to verify existing empirical findings, raising doubts about the generalizability of the conclusions and possible comparative studies. The book is an attempt to clarify the definition of the phenomenon of kindness. It is the result of the first research of its kind and carried out on such a scale in Poland. The main aim of the study was to determine how Polish youth understands the concept of kindness.