In Taiwan, drama assessment and its relationship with pedagogy, quality and the national guidelines have garnered interest and debate since the performing arts became an integral part of "Arts and Humanities" in a major revision of the National Curriculum in 2000. This paper is based upon a collaborative research project with a group of 15 teachers from local schools which intended to develop and understand the process of a performance assessment "for" and "of" learning in the classroom through the summative analysis of a three-year action research endeavour. Data were collected from classroom observations, teachers' feedbacks, group discussions, focus group interviews and reflective notes. The findings suggested that an assessment for drama could be systematically constructed over time to balance the need for alignment between the formative and summative functions of assessments presented in the national guidelines. It was evident that the inclusion of teachers' voices in the process and a constant revision of the rubrics for assessment genuinely responsive to actual practices were key in developing a valid assessment process for drama and thus ensuring better learning quality in the drama programme.