The third edition of "An Introduction to Functional Grammar" presents an updated and accurate account of Systemic Linguistics and its applications to Language Studies. Far from being a complex book, this grammar introduces the reader to a wide range of key aspects of english and its open-ended linguistic questions about clause structure, meaning, and use. So rather than being complex, it is complete. In a threefold perspective, this book depicts language as the realization of a system of linguistic choices as writers or speakers interact with people (interpersonal function) and represent their social and cultural experiences (ideational function) through texts (textual function). What is more, Halliday's and Matthiessen's grammar also presents a fully comprehensive account of clause complexes (noun groups, verbal groups, and coordination and subordination), cohesion (the linkage between lexis, clauses, texts and discourse) and metaphorical modes of expression (language used in its normal structure or metaphorically). It is undoubtedly a very useful resource for Critical Discourse Analysts, Language Teachers, Translators, Corpus Linguists and several qualified professionals who study language and/or live by it.