Intersubjectivity is a central theoretical construct intersecting various disciplines. As a research field it is therefore characterised by its being the meeting point of areas and methodologies even very different from each other. In the history of science, when this sort of overlapping takes place, we witness the gradual emergence of ever more complex theoretical constructs, which can become the conceptual ground for building more general theories.

On the other hand, the interest in the area of intersubjectivity arises from the growing awareness of the intrinsically relational nature of the human species, highlighted by numerous recent discoveries in various fields – e.g., neuropsychology, cognitive science, ethology – so much so that some scholars have coined for our species the term “ultra-social species”.

The landscape of disciplines involving theoretical or experimental research pertaining to the area of intersubjectivity is vast: neuropsychology and neurosciences, consciousness, emotions, embodiment, the “relational” mind, sharing other people's mind states, and more generally various areas of philosophy, ethology, general and evolutionary psychology, social and cultural psychology, clinical psychology and psychiatry, psychoanalysis.

The intersubjectivity construct is therefore utilized on various levels, corresponding to the specific research areas. On one hand, this points to the power and fecundity of the construct; on the other it may be a source of problems – communication, interpretation, explanation and comparison problems – when the meeting involves disciplines that may have, and frequently inevitably do have, different theoretical presuppositions and research methodologies. It then becomes truly important – as wonderfully exemplified by this volume – to build opportunities for comparison and debate, i.e. “frontier territories” where the exchange needed for the growth of shared multidisciplinary knowledge takes place. Such a sharing is essential in order to build more general and more structured theories, whose “fallout” may support the creation or improvement of practical applications or more generally increase our understanding of complex phenomena pertaining to our species.

The issue of practical application is particularly dear to me. When a student asks the Clinical Psychology professor what impact intersubjectivity research has on clinical practice, the answer is that it deals with concepts that are fundamental for the understanding of the therapeutic relationship. They are essential for building that relational field in which the sharing of meaning leading to the therapeutic alliance develops, the field supporting the client's exploration of new ways of functioning and new ways of understanding him or herself in relationship with others. In some particular studies the concept of intersubjectivity has played a crucial role, e.g. the research about autism or that about attachment. But the most relevant aspect for clinical practice is that, when the therapist is aware of her own embodied and intersubjective nature, she will read differently the client's narrative, the client's relationship with her and her own relationship with the client. This applies also to ideas, constructs and relational modalities of the client. Also the therapeutic techniques, such as self-description and autobiography, will have a different meaning and will be more oriented toward viable solutions.

In fact, a good theoretical model improves the use of therapeutic techniques and supports the growth of both self-knowledge and knowledge of the other. This does not just concern the clinicians, but obviously also teachers, trainers, and people operating in a group or institutional contexts or in the media. We need only be reminded of the complexity of the teacher-student relationship, or of the role of an actor in film or theatre. Generally speaking a better understanding of interactive mechanisms can benefit all those who are active in social contexts by providing new and useful conceptual tools. For this reason the present volume, with its high and clear scientific character, by also exploring the frontiers and perspectives of related disciplinary areas, can be of particular interest for a much larger public than the specialised readership.

Prof. Giorgio Rezzonico, Full Professor of Clinical Psychology, Director of the Postgraduate School in Psychiatry, Faculty of Medicine and Surgery, University of Milan-Bicocca, Milan, Italy