Background: Suicide remains the second leading cause of death for adolescents in the United States, and up to 20% of adolescents report nonsuicidal self-injury (NSSI). The Card Sort Task for Self-Harm (CaTS) was developed as a research tool to examine the dynamic interplay of thoughts, feelings, behaviors, and events that are associated with the lead up to self-harm behavior. The CaTS consists of 100+ cards from which individuals select and sort across a timeline ranging from 6+ months to one hour before an episode of self-harm. Previous studies in the UK used the CaTS for self-harm; the current study adapted the CaTS for (NSSI) and suicide attempts (SA) to expand upon prior work. The aims were to 1) identify high frequency cards for NSSI and suicide attempts and 2) compare networks of factors and identify direct pathways to NSSI and suicide attempts. Methods: Data were collected from adolescents at a children’s crisis stabilization unit in the United States who had either past-year NSSI (n=15) or past-year suicide attempt (n=23). The mean age was 14.32 (SD=1.68) and the sample was 72% white (10.3% Black, 8.3% Hispanic/Latinx, 5% multiethnic), 64% female (20.5% male, 15.4% nonbinary/trans), and 31.6% heterosexual (26.3% bisexual, 5.3% gay/lesbian, 15.8% pansexual; 13.2% not sure). All participants were administered the Card Sort Task for Self-Harm and were asked to sort cards along a timeline that led to either their most recent NSSI or most recent suicide attempt. Results: Cards selected at high frequencies (>65%) in both groups were identified. Within the NSSI group, there was great variability in the cards selected and only four that were used by the majority: felt depressed/sad; felt angry; hated self; felt numb. Participants in the SA group had several high frequency cards: wanted to die; no one listened; felt worthless; could not trust others; could not tell others how I was feeling; had access to means. Network analysis for NSSI card sorts showed that “”I felt depressed and sad,” “I felt numb,” and “I hated myself” had the strongest direct links to NSSI. Network analysis for SA showed that several cards had strong and direct links to the attempt; “I felt worthless” and “I felt numb.” There was a strong link from SA to “I felt no different afterward.” Other strong networks included the link between “I wanted to die” and “I was not afraid of death,” and between “I could not trust anyone,” and “I had access to means to hurt myself.” Discussion: Results of the current study provide insight into differences in thought and behavior patterns leading up to suicide attempts vs. NSSI, supporting the notion that these types of self-harm behaviors are distinct. Feasibility and acceptability of potential clinical uses of the CaTS will also be discussed.