The Emotional Literacy Support Assistant (ELSA) programme is an evidence-informed intervention delivered by teaching assistants and supervised by educational psychologists. In this research, semi-structured interviews were conducted to investigate the impact of the ELSA programme on wellbeing from the perspective of pupils. A thematic analysis of the data set identified the following themes: "Feelings and Emotions", "Engagement", "Resilience", "Hopes and Aspirations" and "Relationships". The findings suggest the ELSA programme has a perceived positive impact on multiple components of pupil wellbeing. These components include positive emotions, negative feelings, engagement, resilience, optimism, accomplishment and relationships, as described by the New Economics Foundation (NEF) and Seligman's "PERMA model". The positive wellbeing changes experienced by the pupils occurred through strategies, talking, and forming a close relationship with the teaching assistant. Overall, this research provides evidence to suggest a positive impact of the ELSA programme on pupil wellbeing.