Background: Cultural Safety is a mandatory training requirement for the 16 regulated health practitioners in Australia. Tools measuring outcomes need to be appropriate for different education and training contexts. Aim: To test refinements to the 25 item Cultural Capability Measurement Tool (CCMT). Methods: Framed by decolonising and relational ways of knowing, being, and doing in the tool development process. New items of the CCMT were generated through engagement with key knowledge holders. New items were piloted with expert reviewers and modified accordingly to produce a 41-item scale. Two online surveys conducted with 875 students and then 276 health professionals were collected for analysis. Exploratory factor analysis and a parallel analysis were conducted. Results: The newly named Ganngaleh nga Yagaleh (GY) tool contained 28 items loaded on 3 factors accounting for 47.95% of variance. Factor 1 (Commitment to Culturally Safe Practice; α =.89) comprised 12 items, Factor 2 (Understanding of History and Power; α =.86) contained 9 items, and Factor 3 (Attitudes, Values, and Beliefs; α =.52) contained 7. Total scale reliability was good (α =.87). Impact statement and conclusion: The GY Scale can be used in education and practice settings. Challenges remain about how educational providers and health services approach cultural safety as a life-long learning journey, and how education and clinical practice embed cultural safety standards. Future directions for use of the GY tool include expanding it for use in other contexts and more explicit separation of what is emerging as a separate scale the ‘Keeping Culture Strong’ scale which evaluates the unique learning experiences of First Peoples.