Individuals diagnosed and undergoing treatment for dissociative identity disorder (DID) typically report hearing voices in the absence of any external source, yet this experience is not well understood. This thesis used interpretative phenomenological analysis to investigate the lived experience of voice hearing in the context of the therapy journeys of 12 individuals with DID. Study One (n = 6) broadly resulted in four group experiential themes: ‘voices are communication from different parts of the self with independent identities’, ‘voices emerged as a response to traumatic life events’, ‘voice hearing has negative impacts’, and ‘therapy has offered insights’. A second study (n = 6) explored voice hearing in relation to sense of self and resulted in two group experiential themes: ‘voices are communication of dissociative identities’, and ‘voices diverge from personal ‘owned’ thoughts’. The results of both studies support the notion that the experience of hearing complex, person-like voices may reflect the experience of dissociative fragmentation of self into ‘parts’. Additionally, voices may sometimes be experienced as thought-like, yet will often be differentiated by their unbiddenness, their disconnection from one’s own thoughts, and their ‘not-me’ quality. The findings of this study provide a means for furthering steps in treatment development, and a basis for future investigations.