The authors developed the CFIR by synthesising constructs from multiple implementation theories into a single, coherent framework. The framework identifies five major domains that influence implementation outcomes: intervention characteristics, outer setting, inner setting, characteristics of individuals, and implementation processes. By providing a common language and structure for implementation research, the CFIR helps researchers and practitioners systematically assess barriers and facilitators across different contexts. Overall, the framework has become one of the most widely used tools in implementation science for understanding how evidence-based practices can be successfully adopted, implemented, and sustained.