Inclusion Criteria:  Be in contact with mental health services. Have an identified care coordinator. Meet ICD-10 criteria for schizophrenia, schizoaffective disorder or delusional disorder or meet entry criteria for an Early Intervention in Psychosis service in order to allow for diagnostic uncertainty in early phases of psychosis. History of voice-hearing for a minimum of six months. Aged 16 and above. Score ≥ 2 (i.e. "Voices occurring at least once a day") on the frequency item of the PSYRATS. Score ≥ 3 (i.e. "Voices are very distressing, although subject could feel worse") on the distress intensity rating of the PSYRATS. Confirmed that they consider AVHs, dissociative experiences, and/or trauma as their main problem or presenting difficulty, and that would like to receive a psychological intervention specifically designed to address these difficulties - this will be assessed using four items integrated in the PSYRATS interview administered as part of the present study, and the self-reported therapy goals generated through the CHOICE short form. Score ≥ 1 on any of the items of the Bref Betrayal Trauma Survey assessing lifetime exposure to interpersonal trauma (i.e. items 3-11). scores suggestive of clinical levels of dissociative symptoms, as indicated by a score > 20 on the Dissociative Experiences Scale, time bound Capacity to provide informed consent. Judged by their clinician to be clinically stable for the preceding 4 weeks  Exclusion Criteria:  Any person without capacity to provide written informed consent. If the experience of voices/psychosis is organic in origin (for example, hallucinatory experiences linked to traumatic brain injuries, organic psychoses, or emerging in the context of dementing conditions). Insufficient command of English to complete the research interviews and measures. Intellectual disability, or severe cognitive dysfunction that might preclude the individual's ability to provide informed consent, understand the study procedure and/or fully appreciate the potential consequences of their participation. Primary diagnosis of substance misuse dependency. Where care coordinators identify reasons for why participation might be potentially detrimental. Inpatient/acute care needed.