The phenomenon of gratitude is a characteristic of the human being, which has found expression throughout history in the main religions and has been the subject of philosophical and theological reflection. Gratitude has always been present and it is also present today. Practising gratitude, creating the habit and the benefits of being grateful are becoming fashionable. A first approach to this phenomenon sample how gratitude has as its object "something" - let's say it now in general terms - that has been experienced as positive and that has its origin in the benevolent action of another person. It should be noted that gratitude here is conceived between persons, it is therefore an interpersonal experience that aspires to be expressed to its addressee. Both the experience and expression of gratitude are important for the development and maintenance of healthy relationships (Lambert &Fincham 2011).

The phenomenon of gratitude is also present in the field of palliative care. In the group of research ATLANTES we have developed programs of study systematic topic. The team has shown that gratitude is very present in the interaction with palliative care services (Aparicio, Centeno, Juliá, Arantzamendi 2019). Evidence that gratitude is present in human beings, regardless of their status. It has also studied those elements core topic that patients and relatives thank palliative care teams for in manifestations of spontaneous gratitude; showing that the most human aspects are the ones they are most grateful for (Centeno, Arantzamendi, Rodríguez, Tavares 2010). It has also studied the protective role that professionals attribute to gratitude, which does not depend on the quantity but on gratitude itself (Aparicio, Centeno, Juliá; Arantzamendi 2019).

Considering the depth of the results of the professionals' experiences of gratitude, we have realised the need to go deeper into the concept of gratitude itself, analysing the phenomenon of gratitude itself (and not so much its perception) from the perspective not so much of the recipient of gratitude, but of the subject of gratitude. The present project is part of the priority line of research "Be human" and constitutes an interdisciplinary partnership effort, combining the perspective of professionals in the field of palliative care with that of philosophical reflection.