This study presents a synthesis of empirical research reporting on learners' perceptions about the effectiveness of CMC in EFL/ESL writing classes. Conducting a multi-stage systematic review, we analyzed 52 scholarly research articles published between 2000 and 2016. Our findings indicate that while learners perceive linguistic benefits from interacting with different interlocutors in mainly blog- and wiki-mediated writing activities, they also report challenges with respect to task demands and the quality of feedback. Learners perceive CMC-integrated writing to be authentic and interactive, thereby developing their motivation, autonomy, and identity as writers. Finally, the implications of this review and the directions for future research in the domain of CMC and EFL/ESL writing are discussed.