Background: Treatment options for relapsed or refractory (R/R) anaplastic large cell lymphoma (ALCL) have increased in the era of targeted therapies such as brentuximab vedotin (BV) and Anaplastic Lymphoma Kinase (ALK)-inhibitors. However, there is no standard treatment and limited published data evaluating their use in this patient population. Methods: We conducted a retrospective, multi-institutional study of patients <22 yrs old at initial diagnosis with R/R ALCL treated between 2011-2021 across 18 institutions. Results: We identified 85 patients with R/R ALCL (median age at initial diagnosis 12 yrs, 67% male, 96% ALK+). Treatment for initial diagnosis included ALCL99 (31%), ANHL12P1 + BV (32%), ANHL12P1 + crizotinib (CZ) (11%), ANHL0131 (14%), or other (13%). Median time from diagnosis to relapse was 0.7 yrs (range 0.2-10.8 yrs) with sixteen patients (18%) relapsing on initial chemotherapy. Stage at relapse for 82 ALK+ patients: I (9%), II (15%), III (41%), IV (35%). Initial re-induction regimens shown in the table. Fifty-nine (72%) patients received a hematopoietic stem cell transplant (HSCT), 11 autologous and 49 allogeneic with one receiving both. Of 59 transplanted patients, 10 relapsed (6 allo 4 auto) and 7 died. All but one of the patients who relapsed post-HSCT responded to additional therapy and remain alive. Of 23 ALK+ patients who never had a transplant, 4 patients died and 19 are alive in remission. Eleven remain on active therapy (6 CZ, 3 BV, 1 BV+CZ, 1 vinblastine) with eight off therapy. Patients who received a transplant more likely to be off therapy and alive. Duration of treatment for patients receiving BV or the ALK-inhibitor CZ varied widely (BV 1-11 yrs; CZ 2-10 yrs) with 20 patients continuing on therapy at the time of data collection. Five-year overall survival for patients with or without transplant was 91% (CI 84-99%) and 86% (CI 73-100%) respectively. Conclusions: This is the largest collection of patients with R/R ALK+ ALCL treated in the era of targeted therapy. Patients achieved excellent responses to ALK-inhibitor or BV monotherapy, but questions remain about duration of therapy. Transplant may not be necessary for all R/R patients including those with high-risk disease.