The main aim of the study is to explore the role of self-assessment in EFL learning in developing lifelong language learning skills and in furthering the development of more comprehensive and thereby fairer assessment practices. The study explores how students perceived their own general and specific writing abilities in relation to syllabus goals and whether these perceptions are affected by self-assessment practices. The study is based on the theory that metacognitive skills are important for the development of autonomous learning skills. Two teachers and four groups of Swedish upper secondary students participated in the study during one school year. Using grades, students self-assessed the results of two written assignments. The teachers and eight student groups were also interviewed about their experiences. The results showed that at a group level the students were well able to assess their general writing results. At the individual level the results were more variable, partly depending on the type of writing activity assessed and the amount of self-assessment practice the students had had. The students and teachers were positive to the incorporation of self-assessment activities in the EFL writing classroom and saw it as a transferable skill that underpins lifelong learning in other subject areas. Self-assessment was considered as contributing valuable additional information to ordinary tutoring and testing. The implications are that syllabus goals that encourage student responsibility and autonomy are viable and realistic but students need to practice self-assessment to become adept at employing the approach. Five appendices are included: (1) Abbreviations and Glossary of Terms Used; (2) Information [written in Swedish]; (3) Classroom Writing Assignments [portions of this appendix are written in Swedish]; (4) Self-assessment after Writing Test A / B (SAWT) [written in Swedish]; and (5) Interview Questions [written in Swedish]. (Contains 24 tables and 19 figures.)