276 Background: Poor communication between referring physicians and consultants can lead to disruptions in continuity of care, unnecessary testing, and iatrogenic complications. We sought to identify the barriers to effective communication between Indiana University Simon Cancer Center (IUSCC) oncologists and ROs. Methods: We retrospectively analyzed communication surrounding the visits of consecutive new oncology patients (pt) to IUSCC during Dec 2017 and Jan 2018. Demographics, diagnoses, RO’s information, and IUSCC physician’s information were recorded from the electronic medical record (EMR). ROs were contacted and a questionnaire was administered about timeliness, methods, and satisfaction with the communication. Results: A total of 110 new pt consultations were undertaken during the study period. There were 9 self-referrals, 69 interfacility referrals from the IU Health system, and 32 referrals by community RO. We were able to reach 27 community ROs, and their comments were included in the final analysis. RO interviews revealed that 78% had received notes (21 of 27 visits). Median time from pts’ clinic visit at IUSCC to ROs receiving a note was 2.5 days (range, 0-38 days). Five (25%) notes were received on the same day of consultation, and 10 (50%) were received within 2-7 days from pt visit. Of 18 traditionally dictated notes, 16 (89%) were received by ROs. Of 9 EMR typed notes, 5 (55%) were received by ROs. Only 62% of ROs received notes when their information was missing in the EMR. Based on feedback from ROs, effective communication was defined as communication within 7 days from pt visit. Ineffective communication was seen mostly on Mondays, followed by Fridays (75% and 50%, respectively). Conclusions: Effective communication was achieved in 75% of consultations. Effective communication was impacted by the day of the week, accuracy of RO information in the EMR, and the method of note documentation. Correcting ineffective communication can be explored through improvement of both human factors (ex.reinforcement of timely communication goals with physicians) and system factors (ex. Improving the accuracy of RO data in the EMR). Checklists, audits and other process analytics may help overcome the barriers identified.