The focus on communication in TBLT often comes at the expense of form. In this book, the task-based approach is enhanced and coupled with insights into (cognitive) grammar, an approach which sees grammar as meaningful. The book shows how grammar teaching can be integrated into a communicative lesson in a non-explicit way, i.e., "by the backdoor". The learners are involved in situations that they may also encounter outside their classrooms and they are given communicative tasks they are to work on and solve, usually with a partner or in small groups. What teachers need to invest for preparing such lessons is their own creativity, as they have to come up with communicative situations which guide the learners into using a specific grammatical structure. The book first discusses the didactic and the linguistic theories involved and then translates these theoretical perspectives into actual teaching practice, focusing on the following grammatical phenomena: tense, aspect, modality, conditionals, passive voice, prepositions, phrasal verbs, verb complementation, pronouns, articles.