Children and young people in care and people who are addicted to substances are two of the most marginalised groups in society. Both groups often experience childhood trauma and adversity and experience stigma and disadvantage. This thesis aimed to hear the voices of both of these groups. Part A of this portfolio presents a systematic review of the educational experiences of children and young people in care. The findings of this review suggest that being in care impacted on the children and young people’s educational experiences. Children and young people in care also voiced experiencing pervasive disadvantage and stigma whilst accessing education and stressed the importance of relationships in impacting on their experiences in education. Part B of this portfolio presents an empirical paper which is a mixed methods proof-of-concept study. This investigated the acceptability and feasibility of a CBT informed intervention for opiate substitution treatment within an NHS specialist addiction service. The findings suggest that the intervention was acceptable and feasible both for service users to engage with and for clinicians to deliver. Qualitative results indicated that both anxiety around being without opiate substitution treatment and support from the prescribing service were barriers to deprescribing opiate substitution treatment.