The study explored psychologists' experiences in delivering short-term psychotherapy for suicidal adolescents and sought to clarify how these experiences fit with empirically supported interventions and the interpersonal psychological theory of suicide. Semistructured interviews were conducted with 12 psychologists' who provided short-term psychotherapy in a suicide prevention programme for youth (12- to 25-year-olds). Interview transcripts were analysed using interpretative phenomenological analysis. Three superordinate themes were identified: (i) understand the experience and context of the suicidality and the importance of a formulation-based approach to engagement and individualized treatment planning; (ii) involve broad support systems, and in particular families, to help the young person reduce feelings of burdensomeness and increase safety, connectedness and belonging; and (iii) improve affect regulation and reflective functioning, important not only for the young person but also for the support system to maximize the positive impact of supports via emotional coregulation and effective problem-solving. Interventions and approaches as well as the potential underlying processes of change being targeted are discussed in light of these findings. As an example, the development of a suicide safety plan was an intervention that traversed these themes. When used as a process tool, it helped foster a collaborative, formulation, dimensional and biopsychosocial approach to treat psychopathology and suicidality and extended beyond the therapist–client dyad. Moreover, treatment needs to be extended beyond the therapist–client dyad to allow therapists to facilitate a systemic treatment response, as this was seen as a major component of interventions for suicidal youth.