Critical Review of the Literature Adolescents with mental health problems frequently report disturbed sleep. Despite the emerging evidence that sleep is a contributory factor of mental health problems, the treatment of insomnia in adolescents is a relatively overlooked topic when compared to the adult literature. The current review aimed to examine the emerging literature on the impact of Cognitive Behavioural Therapy for insomnia (CBTi), the first line recommended treatment for insomnia, on sleep and psychiatric symptoms in young people. An additional aim was to examine the acceptability of CBTi to young people and to describe any adaptations to the intervention that are employed to address adolescent developmental changes. Systematic searches of PsychINFO, Medline, EMBASE, and Scopus databases were performed to capture the key search terms of i) young people, ii) insomnia, and iii) sleep intervention. Studies were required to include a quantitative measure of insomnia and at least one psychiatric symptom at pre- and post-treatment. Eighteen studies (n=8 controlled, n=10 uncontrolled) were identified. The majority of studies (n=14) were given an overall quality rating of ‘fair’. Results found promising effects for self-reported insomnia and psychiatric symptom outcomes, specifically large effects on depression and smaller effects on anxiety. CBTi led to improvements in behavioural problems and psychosis related outcomes but this was only assessed in a small number of studies. CBTi appears an acceptable intervention to adolescents, however adaptations to address developmental changes were rare. Further good quality, controlled studies are warranted in clinical populations. Service Improvement Project Background Adolescents with mental health problems frequently report sleep disruption and there is increasing evidence that sleep is a contributory factor in the occurrence of mental health problems. Despite this, sleep is frequently overlooked as a treatment target. Adolescent inpatient wards present additional challenges to sleep, yet little is known about sleep problems in this setting. Mixed-methods were used in two linked studies. Study one examined the prevalence of insomnia at admission in adolescent inpatients, and cross-sectional associations with psychiatric symptoms and admission length. Study two sought the perspectives of ward clinicians on patients’ sleep. Method Data from 100 adolescent inpatients, aged 11-17 years, were gathered from admission routine outcome measures and medical records. Associations were analysed using a series of linear regressions. A clinician focus group and qualitative interviews were conducted and analysed using thematic analysis. Results Fifty percent (n=50) of the sample screened positive for insomnia. Moderate to large significant associations were observed separately between insomnia severity and the severity of depression (β=-0.56), anxiety (β=-0.51), self-harm (β=-0.49), psychotic experiences (β=-0.32), and conduct problems (β=-0.30), but not admission length. Qualitative data identified three key themes: i) the experience of sleep problems, ii) barriers and facilitators of sleep, and iii) managing sleep problems on the ward. Clinicians described a reciprocal relationship between insomnia and psychiatric symptoms. Although a psychological intervention was viewed as potentially helpful, limited capacity meant this was not routinely offered. Sleep hygiene, melatonin, hypnotic and psychiatric medications were typical treatment responses. Conclusions Insomnia was prevalent in this adolescent inpatient sample. Existing psychological interventions require adapting to overcome the barriers to sleeping on a ward. Improving sleep is important in and of itself, but there are potential benefits for risk management and alleviating psychiatric symptoms which require testing. Theoretically Driven Research Project Background: The Covid-19 pandemic has had a negative impact on the populations mental health particularly for individuals with Health Anxiety (HA) and Obsessive Compulsive Disorder (OCD). This is in conjunction with a significant change in accessibility of face-to-face psychological services which have had to rapidly adapt to the remote delivery of therapy. Aims: The study aimed to evaluate the effectiveness of evidence based CBT interventions for HA and OCD delivered via a blend of online therapist consultations interspersed with self-study reading materials. A secondary aim was to evaluate remote training workshops provided to therapists. Method: Therapists attended 3 half day remote workshops after which consecutive participants with HA or OCD were assigned to therapists for treatment. Monthly expert supervision was provided. Patients completed routine outcome measures at each session and an idiosyncratic measure of preoccupation with Covid-19 at pre- and post-treatment. Results: Significant and comparable improvements were observed on measures of anxiety, depression and social adjustment from pre- to post-treatment in both the HA (n=13) and OCD (n=20) groups. Disorder specific measures also showed significant improvements after treatment. The HA group showed greater levels of change the Covid-19 specific questionnaire. The training workshops were well received by therapist who valued the monthly supervision sessions. Conclusions: The study provides support for the effectiveness of the online delivery of CBT for HA and OCD supported by the inclusion of additional self-study booklets.