The Attempted Suicide Short Intervention Program (ASSIP) has been shown to be effective in reducing the risk of new suicide attempts compared to a single suicide risk assessment session, both in addition to treatment as usual (Gysin-Maillart et al., 2016). The intervention has recently been qualitatively evaluated in a report on patients' experiences of the short-term impact of the treatment (Gaily-Luoma et al., 2023). This evaluation described ASSIP as a highly valuable add-on treatment for suicide attempt survivors with a suicide-specific focus that facilitated remoralisation, the creation of reliable safety strategies and motivation to engage in further life-affirming efforts. However, further evaluation is needed, involving the long-term effects of ASSIP based on patient experience, in addition to the later part of ASSIP with the ongoing contact by regular letters, which have not yet been evaluated. In this presentation, we will outline the preliminary results of a multicentre study aiming to qualitatively evaluate the entire two-year ASSIP treatment including the follow-up by letters. Using inductive qualitative content analysis, the study is based on longitudinal in-depth interviews with patients who have received ASSIP treatment. Participants were recruited with a balanced gender and age distribution, and each participant (N=15) was invited for two in-depth interviews - one after completion of the three ASSIP sessions and one at the end of the follow-up two years later. The presentation will try to address the potential factors contributing to the effectiveness of the treatment based on the patients' experiences. References Gaily-Luoma, S., Valkonen, J., Holma, J., & Laitila, A. (2023). Client-reported impact of the Attempted Suicide Short Intervention Program. Psychotherapy Research, 1-14. https://doi.org/10.1080/10503307.2023.2259070 Gysin-Maillart, A., Schwab, S., Soravia, L., Megert, M., & Michel, K. (2016). A Novel Brief Therapy for Patients Who Attempt Suicide: A 24-months Follow-Up Randomized Controlled Study of the Attempted Suicide Short Intervention Program (ASSIP). PLoS medicine, 13(3), e1001968-e1001968. https://doi.org/10.1371/journal.pmed.1001968