The purpose of this randomized controlled trial was to determine the effects of pre-transplant music therapy on distress, pain, anxiety, mood, quality of life (QOL), and pain medication use during the preparation period for hematopoietic stem cell transplant (HSCT). Distress, the primary outcome, was measured via the Distress Thermometer. QOL was assessed with the Functional Assessment of Cancer Therapy – General 7 (FACT-G7). Participants self-rated pain and anxiety on Numeric Rating Scales (NRS) and mood on the Rogers Happy/Sad Faces Scale. Participants randomized to the experimental group received three music therapy sessions prior to stem cell infusion day. Repeated measures analysis of variance (RMANOVA) was employed to detect differences between groups for distress and QOL, and t-tests were used to detect differences between groups for pain, anxiety, and mood. Data collection is ongoing and will conclude when 50 patients have been accrued. This report presents interim data analysis, with complete data available for 23 participants. The experimental group had higher distress that was statistically significant at baseline and on Day -1. Music therapy did not affect distress but showed other limited beneficial effects. There were no differences between groups at any individual time point for pain, anxiety, or mood. At all three time points, decreases in anxiety from pre-session to post-session assessment were statistically significant in the experimental group. In the first and third music therapy session, differences between pre- and post-session mood scores were statistically significant in a positive direction. Differences in pain medication use could not be calculated because too few participants required pain medication. Although music therapy did not affect the primary outcome of distress, the positive short-term effects on anxiety and limited positive effects on mood are important to acknowledge. The small sample size likely contributed to the lack of findings on distress, although the longitudinal assessment of this outcome may have also been a factor. This study provides an initial understanding of how music therapy may be effective on distress and other variables during the pre-transplant hospitalization period for patients undergoing allogeneic HSCT, as it is the first research study to examine this treatment phase. There are few music therapy research studies with patients undergoing HSCT, which leaves many options for future research. It would be worthwhile to explore any short-term effects of music therapy on distress and QOL, as well as longitudinal effects on anxiety and mood. Optimal music therapy session duration and frequency during the pre-transplant hospitalization period remains unknown. Research opportunities exist during other phases of HSCT treatment, such as the out-patient pre-transplant period, duration of hospitalization, or post-transplant follow up. Understanding the effects of music therapy for patients suffering from Graft-Versus-Host Disease could also be beneficial as this is often debilitating and can be life-threatening. Finally, there is a need for qualitative music therapy studies with this patient population, as none currently exist but could provide additional insight for future research studies as well as clinical practice. / Music Therapy