The study examines the use of feedforward-based collaborative assessment (FbCA) for students majoring in foreign languages at a tertiary institution in Vietnam. A mixed-method research approach was utilized to collect both quantitative and qualitative data from 306 English major students and eight teachers. Research instruments such as questionnaires, reflective diaries, observations, and interviews were employed to assess the perceptions of students and instructors regarding the significance of implementing FbCA, its impact on students' learning engagement and academic achievement, and students' expectations for changes in assessment mechanisms to ensure the effective use of FbCA. The findings highlighted several benefits of FbCA in terms of skill, knowledge, and practice development. This evaluation approach enhanced students' learning motivation and positively contributed to their academic performance. However, the qualitative data also revealed various challenges related to the effective implementation of assessment practices and the maintenance of academic integrity. Based on these findings, recommendations were made for improving teaching, learning, and assessment practices. [Note: The page range (335-352) shown on the PDF is incorrect. The correct page range is 335-351.]