Identifying what is important in the self-interpretations of young people who report no religion, this study examines how relationships of difference to religion relate to matters of importance. Twenty-three Year 10 pupils (14- and 15-year-olds) from two non-denominational secondary schools in the West Midlands who ticked the 'no religion' box on a questionnaire were asked to take photographs to represent what was important to them. These were used as prompts for discussions during one-to-one interviews that explored what was important to these young people, before asking questions about religion and their reasons for reporting none. Taking a relational approach to the study of non-religion (Lee 2012a; Quack 2014), this thesis identifies participants' relationships of difference to their constructions of religion. Understanding identity as a self-interpretation relating to things that matter to us (Taylor 1989), it determines whether and how relationships of difference are significant in participants' self-interpretations and how, therefore, ticking the 'no religion' box on a questionnaire relates to issues of identity. Participants' constructions of religion and their decision to report none were influenced by what they considered to be matters of importance, and what they considered to be important was reflected in their beliefs about life, the end of life, life after death, God, the supernatural and prayer. While many participants held beliefs adapted from religious traditions, they considered these to be different from those they associated with religion. The question of whether participants expressed non-religious identities depends on the relative significance of relationships of difference to religion in participants' self-interpretations. For the majority of participants, relationships of difference to religion were not of central importance, meaning that very few should be categorised as having non-religious self-identities. Implications are drawn for the study of youth, religion and non-religion and for the teaching of religion and belief in schools.