Non-suicidal self-injury (NSSI) is recognized as a public health concern owing to its chronic nature, association with suicide risk, and its growing prevalence rates across the globe. Including individuals living with NSSI in research is crucial as it offers opportunities to give primacy to participant voices and insights, further guiding therapeutic interventions. Research has established an association between history of traumatic events and adverse childhood experiences with subsequent risk of NSSI. When planning a qualitative research study with individuals with potential trauma history, researchers need to be aware of and sensitive to potential re-traumatization and distressing emotions that participants may experience during interviews, as well as complex trauma reactions that may affect individuals after study participation. The article emphasizes that researchers be cognizant of the multifaceted nature of trauma and how it can impact individuals and communities and be sensitive in their approach to interviewing vulnerable groups such as individuals with experiences of NSSI. The authors propose adopting a trauma-informed approach to ethically plan and conduct qualitative interviews exploring NSSI experiences. Trauma-informed recommendations for preparing and carrying out specific steps during different stages of NSSI interviews are detailed.