Background: The Northwestern Medicine Breast Cancer Quality Improvement Collaborative (NM BCQIC) is a novel health system-wide QI collaborative of 5 hospitals developed to equip providers with the knowledge and skills to identify and improve upon their local performance gaps in breast cancer care. NM BCQIC undertakes collaborative-wide QI projects to improve adherence to best practice guidelines, quality of care, and outcomes while reducing clinical variation across the health system. Collaborative participants generally had little formal training and variable experience with QI prior to joining NM BCQIC. Our objective was to evaluate baseline QI knowledge of oncology providers participating in a multi-institutional QI collaborative. Methods: An oncology-focused adaptation of the QI-KAT (Quality Improvement Knowledge Application Tool), a validated QI knowledge assessment with multiple choice and free-responses sections, was administered through REDCap to NM BCQIC members shortly after collaborative inception. Four members of the NM BCQIC Coordinating Center scored each de-identified exam utilizing a rubric-based scoring tool (50 total points). Discrepancies in scores were discussed until consensus was achieved. Results: Of the NM BCQIC members eligible to complete the QI-KAT, 72.7% (16 out of 22) completed the assessment. The mean overall score was 69% with a median score of 66%; individual scores ranged from 40% to 96%. Several common themes were identified: (1) a majority of participants successfully identified the quality problem and were able to create an effective statement to communicate the problem; (2) most were able to the appropriate stakeholders in a QI initiative; (3) many had difficulty recognizing drivers of poor performance; and (4) many struggled to articulate how to institute an effective change in the system in order to improve performance. Individual reports were distributed to participants with personalized feedback on their strengths and areas for improvement. Conclusions: Administering an adapted QI-KAT to oncology providers participating in a multi-hospital breast cancer-focused QI collaborative revealed that they generally lack knowledge in how to effectively carry out QI. The QI-KAT provides specific information and themes that can be utilized to develop a focused educational curriculum to equip participants to implement and sustain successful cancer-focused QI initiatives.