Among the essential conditions for language learning are motivation, exposure and use. Formal instruction or class-room based teaching is said to be only the desirable (not essential) condition. Learners will anyway learn a language whether or not taught in formal classroom settings if they have motivation, exposure and opportunities to use the target language. This is precisely the aim of the present paper – to discuss the challenges and roles of a language teacher in the classroom especially in the wake of the predominance of communicative language teaching (CLT) methodologies. The paper first discuss the principle of CLT and then moves on to explore in to the challenges and roles of a language teacher spread across three domains: the competence domain, the pedagogic domain and the affective domain. The competence domain concerns subject matter knowledge and skills/ knowledge update. The pedagogic domain pertains to lesson planning and classroom management. The affective domain includes personality traits and attitude concerns. The paper ends with an appeal to all language teachers to contribute to the cumulative, consistent and mutual professional growth of everyone involved in the art of language teaching.