This paper seeks to understand the contextual influences that were considered important for shaping teachers' use of Assessment for Learning (AfL). Using the micro, meso and macro-level contextual framework, the content analysis of teachers' propositions drawn from semi-structured interviews and three group discussions unveiled both internal and external-to-school factors. Internally, the factors were associated with the students, teachers, resources at school and admission issues. A lack of ongoing involvement and support from the government and parents was mentioned as an external determinant. Besides considering these influences as barriers to innovation, teachers reported some potential opportunities that enabled them to perform assessment innovation, but evidence for the barriers outweighed the opportunities, which led to the perception that the reform was difficult to carry out. This implies that teachers' approach to the AfL initiatives would rely heavily on the shallow approach of implementation. The study recommends that the incremental approach to reform implementation and sustainable professional development would need to be promoted to address the implementation barriers.