Background: The Northwestern Medicine Breast Cancer Quality Improvement Collaborative (BCQIC) is a novel health system-wide QI collaborative of 5 hospitals. The primary goal of BCQIC is to improve guideline adherence, quality of care, and outcomes while reducing variation health system-wide. Organizational- and unit-level readiness for change, including the extent to which members are prepared to implement a new QI project, is often overlooked. Our objective was to assess the readiness of each BCQIC hospital and their QI teams to locally implement a collaborative-wide project to improve NCCN Guidelines adherence by creating and implementing a system-wide standard for indications and timing of referral of breast cancer patients to genetic counseling. Methods: We adapted a QI Readiness Assessment Tool (RAT) created previously by our research group. The purpose of the RAT was to collect baseline data of local providers’ perceptions of their hospital’s willingness and ability to change practice. The RAT uses a 5-point Likert scale of agreement to assess areas where local QI teams perceive a need for guidance in project implementation, and where units or specialty areas within the hospital may need assistance in process improvement execution and change management. All BCQIC QI team members at each hospital were asked to complete the RAT, which was administered through REDCap. Results: Of the BCQIC members eligible to complete the RAT, 72.7% (16 out of 22) completed the assessment. The hospital-level survey response rates ranged from 50% to 100%. Common themes identified among QI teams at all hospitals included difficulty with: 1) setting specific implementation goals; 2) clarifying team roles; and 3) developing project management documents. At the specialty/unit-level, perceptions of readiness to implement the QI project were strong, overall; however, one hospital unit (Genetic Counseling) identified a need to strengthen understanding of how the project would personally benefit individuals. Conclusions: Perceived implementation strengths, resources, and barriers have the potential to facilitate, delay, or prevent QI project progress and success. Assessing local QI teams’ perceptions of their unit- and team-level readiness to implement a complex QI project provides an opportunity to gain insight into local QI assets and unanticipated barriers. Tailored tools can then be developed to strengthen targeted areas to support implementation success.