The present study aimed to compare the nature of peer-peer dialog among two Iranian (EFL) and two Malaysian-Chinese (ESL) dyads during eleven collaborative writing sessions. Their pair talks were audio-video-recorded, transcribed verbatim and subsequently were analyzed at three levels: type of talk, type of activity and type of episode. The types of talk were sub-segmented into three kinds of talk: on-task talk, about-task talk and off-task talk. Analysis revealed that on-task talk was the most frequent, while off-task talk was the least common across all dyads. As for the type of activities, the process of collaborative writing was found segmentable into three stages of planning, writing, and revising, although there were instances when this linear three-stage process was flouted and also the time that dyads spent on each activity varied. In terms of taxonomy of episodes, about-task talk and on-task talk episodes were the same among all the dyads. As for the Language Related Episodes (LREs) generated in the course of peer-peer dialogs, despite being identical in terms of the typology, there was a notable difference in frequency between Malaysian-Chinese and Iranian dyads. In contrast to their Malaysian-Chinese counterparts, Iranians exhibited a stronger tendency to engage in discussions about the meta-linguistic aspects of language. The findings hold potential pedagogical significance and implications for language learning teachers, researchers and practitioners.