Online Communities of Practice (OCPs) are among the most accessible tools for EFL/ESL teachers' co-construction of knowledge and self-directed learning. Despite the welcomed proliferation of EFL/ESL teachers' OCPs, concomitant research on collaboration is noticeably lagging behind. The present paper is just a preliminary look at moderation and participation, two of the most salient roles of members in OCPs. The authors co-moderate a local Yahoo group of EFL teachers from Venezuela, and participate in an international Yahoo Group of EFL teachers from different countries and nationalities. By analyzing (a) the posts the authors wrote in each OCP and (b) the authors' introspective accounts completed for the purpose of this research, it appears that contrary to expectations there is not much difference in executing the roles of moderation and participation. Results indicate that, rather than changing their online behavior and style while embarking in the two tasks, each author appears to display similar behavioral tracts in both OCPs. Because English is the language of collaboration in both OCPs, results suggest that participation and moderation in OCPs may serve as a deterrent of language loss. The paper concludes with a call for more research on the role of EFL/ESL teacher-teacher interactions in OCPs. (Contains 1 table.)