Professional development programmes that include teacher collaboration can help teachers meet their professional needs and control their professional lives. They can voice their needs and expectations to peers who share similar experiences. Moreover, teachers can discover new teaching roles and opportunities, develop new skills and find motivation in being a member of a group (Burbank & Kauchak, 2003; Hawkes, 2000). With the affordances provided by Web technologies, the potentiality of online communities of practice (CoPs) as a means of improving teacher professional development has become a reality and is gaining popularity. The Online Continuing Professional Development for Teachers (e-CPDelT) project aimed to develop three online CoPs; that is, English, Mathematics and Science communities among twenty Malaysian Smart school teachers. This paper examined the key CoP dimensions, as expounded in Wenger's (1998) framework, and investigated whether their presence is sufficient for successful CoP among teachers in the English cohort. The findings revealed that although the key CoP dimensions were present, there were several factors inhibiting their participation in the community-based cohort. It can be implied that it is crucial to consider these factors in developing teacher online CoPs in Malaysia.