ABSTRACT: BACKGROUND:Remote delivery of psychological interventions to meet growing demand has been increasing worldwide. Telephone-delivered psychological treatment has been shown to be equally effective and as satisfactory to patients as face-to-face treatment. Despite robust research evidence, however, obstacles remain to the acceptance of telephone-delivered treatment in practice. This study aimed to explore those issues using a phenomenological approach from a patient perspective to identify areas for change in current provision through the use of theoretically based acceptability and behaviour change frameworks. METHODS:Twenty-eight semi-structured interviews with patients experiencing symptoms of common mental health problems, waiting, receiving or having recently received telephone-delivered psychological treatment via the UK National Health Service's Improving Access to Psychological Therapies (IAPT) programme. Interviews were recorded, transcribed verbatim, and analysed using the Theoretical Domains Framework (TDF) and Theoretical Framework of Acceptability (TFA). RESULTS:The majority of data clustered within five key domains of the TDF (knowledge, skills, cognitive and interpersonal, environmental context and resources, beliefs about capabilities, beliefs about consequences) and mapped to all constructs of the TFA (affective attitude, ethicality, intervention coherence, self-efficacy, burden, opportunity costs, and perceived effectiveness). Themes highlighted that early stages of treatment can be affected by lack of patient knowledge and understanding, reservations about treatment efficacy, and practical obstacles such as absent non-verbal communication, which is deemed important in the development of therapeutic alliance. Yet post-treatment, patients can reflect more positively, and report gaining benefit from treatment. However, despite this, many patients say that if they were to return for future treatment, they would choose to see a practitioner face-to-face. CONCLUSIONS:Using a combination of theoretically underpinned models has allowed the identification of key targets for change. Addressing knowledge deficits to shift attitudes, highlighting the merits of telephone delivered treatment and addressing skills and practical issues may increase acceptability of, and engagement with, telephone-delivered treatment.