Due to its demonstrated potential to enhance student learning and self-regulatory development, Assessment for Learning (AfL) has emerged as a cornerstone of educational reform across diverse national contexts [Black & William (Curriculum Journal 16:249–261, 2005). However, empirical studies reveal persistent challenges in its implementation, marked by inconsistencies and inadequate adoption in practice. This chapter synthesizes research on AfL implementation across Western and Eastern educational settings, with particular attention to Chinese classrooms. By analyzing these empirical studies, the chapter identifies key barriers and enablers influencing AfL uptake. Specifically, it highlights teacher assessment literacy and teacher assessment capability as two critical factors shaping effective AfL integration.