Mentalization is a concept that integrates psychoanalytic thinking with attachment theory and cognitive theory, among others. The ability to mentalize is developed through, and dependent on, a secure attached relationship, and gives the person the capacity to view and understand both oneself and other people’s internal mental states such as emotions, needs, motives, beliefs, thoughts, etc. Mentalization gives the person the ability to distinguish between the inner and outer reality, which is in closely connected to identity through the interaction of selfreflection and interpersonal components. When a person has insecure attachment patterns, the capacity of mentalization can be diminished, and therapy for the development of the ability to mentalize may be deemed necessary in order for the person to become more confident being in the world as an independent, defined, individual. These difficulties are often seen in individuals with personality disorders, but some of the issues may also be seen during adolescence, because of the emergence of identity crisis following development from childhood to adulthood.

Purpose: The purpose of this master thesis is to examine how mentalization, as a part of emotional identity development, can be understood through the use of Songwriting during music therapy with a teenager placed in foster care.

Method: To answer the above question, a single-case study is examined in a qualitative inquiry, inspired by both a hermeneutic and phenomenological approach. The concepts of attachment, affect attunement and mentalization will be examined through theory according to the purpose of the research as well as through a review of existing literature on Songwriting. The case is defined by a Songwriting process in music therapy with a 15 year old girl, during the investigator’s internship.

Data: The data in this investigation consist of the lyrics of the song, composed within a music therapy session, with the investigator as the therapist, along with selected samples of conversations from the music therapy sessions. The data material is gained from audio and video samples, and presented in the thesis text as transcriptions. These examples are analysed using a modified model of mentalization-based treatment (MBT) by Anthony Bateman & Peter Fonagy (2007) to examine levels of mentalization, and two models designed by the investigator, to explore attachment patterns and voice parameters.

Results: The results of the investigation show that it is possible to analyse and achieve understanding of levels of mentalization through the use of Songwriting in music therapy, given the platform of both verbal and musical interventions. This symbiosis facilitated the possibility of emotional understanding regarding both the client herself and others, which is closely connected to mentalization abilities. The investigation confirmed that attachment is closely related to the mentalization processes and therefore enlightening for the insight of these. Furthermore, it showed that the voice can be a clarifying channel for a deeper understanding of mentalization.