Using portfolio assessment to enhance teaching and learning of writing has been ongoing for more than two decades. Despite extensive research on portfolio assessment, not much attention has been paid to its wider implementation in EFL writing settings where alternative assessment is rarely encouraged. This paper fills this gap by arguing that when portfolio assessment is put into practice, writing teachers may encounter a myriad of individual, institutional, and broader contextual issues. The paper starts with an introduction of portfolio assessment in education, followed by a discussion on the what, why, which, how, and when aspects of writing portfolio assessment. Then, it comprehensively evaluates the individual (teacher assessment knowledge and skills), institutional (curriculum design and school support), and systemic issues (educational policy and culture) within a context of portfolio assessment scholarship. Based on the review of these multi-level issues, pedagogical implications are discussed. Lastly, five actionable goals are recommended relating to how portfolio assessment can be pragmatically utilised to inform teaching and learning of writing.