Background: Despite national guidelines advocating that patients (pts) with advanced cancer receive dedicated palliative care (PC) services, many pts lack access to specialty PC, due to PC workforce shortage. Training hematology-oncologists (HOs) to provide primary PC could close this gap and ensure basic PC needs of pts are met. While HO fellowships require demonstration of competence in PC skills, studies have shown major deficits in PC knowledge, educational experiences and confidence. We designed a longitudinal, integrated, PC continuity rotation for HO fellows. We report feasibility, acceptability, perceived value, and impact on knowledge and practice of this novel educational model. Methods: Over 6 months, HO fellows identified patients with PC needs from their HO continuity practice and referred them to PC clinic. Fellows then saw those pts in PC clinic with the PC attending and in HO clinic with the HO attending, as well as during hospitalizations. Pt visits and HO fellow participation were tracked for feasibility. Fellows were surveyed before and after the rotation on skill confidence and knowledge, which were compared using generalized linear models for unmatched data. After the rotation, they were surveyed on acceptability and teaching quality; they also participated in a semi-structured interview assessing educational value. Fellows electronically gave informed consent for participation; the project was approved by the institutional IRB. Results: From 2018-2023, 19 fellows from 3 HO fellowship classes participated. All 19 referred 2-4 of their continuity oncology pts to the PC team and then followed these pts in both clinics longitudinally over 6 months. A total of 51 pts (#fellows-#pts: 9-2 pts; 7-3 pts; 3-4 pts) had a total of 132 PC visits. Fellows participated in 125/132 PC visits (95%); the majority were outpatient (94/132; 71%). From pre to post intervention, there was an improvement in fellows’ PC knowledge (mean 6.44/10 to 7.92, p<0.01) and overall feeling of preparedness to provide PC (mean 6.33/10 to 7.75, p<0.01). Ratings of skill confidence improved in 14 of 26 items (p<0.05), including titration of opioids, managing pain in pts with substance use disorder, recognizing when to consider methadone, and working with an interdisciplinary team. Of 17 fellows rating acceptability, 16 (94%) rated the rotation as valuable or extremely valuable, 15 (88%) agreed or strongly agreed the rotation structure was effective, and 17 (100%) agreed or strongly agreed the rotation both changed their clinical practice and helped them feel more engaged in working with their sickest pts. Conclusions: Our pilot study of a novel, longitudinal, integrated, PC continuity rotation for HO fellows was highly feasible and acceptable. The rotation changed clinical practice and improved fellows’ PC knowledge and skill confidence. This could serve as a model for integrating PC education into HO fellowships nationally.