This volume has been designed to illustrate the wholistic perspective on language description afforded by Systemic Functional Linguistic (hereafter SFL) theory. Part I focuses on grammatical description, in studies of Mongolian, Classical Tibetan, Chilean Spanish, Brazilian Portuguese and Tagalog. Part II focuses on the contextualization of such descriptions in relation to higher levels of analysis (discourse semantics, register and genre), multilingual discourse (in an EFL classroom) and semiosis beyond language (mathematical symbolism in particular)—with reference to English, Spanish, Chinese, Pitjantjatjara, Oromo and Indonesian. In this introductory chapter we will provide a brief outline of the SFL model of language informing these discussions and then introduce each contribution in more detail. We conclude with consideration of the contribution of this volume to functional linguistic theory and description.