The concept of communicative competence has been rendered as context-abstracted code-bound knowledge for language teaching and assessment. This Element offers a different perspective on 'communication' and 'competence'. Part I offers the rationale for this re-orientation. Part II examines the conceptual and pedagogic affordances and delimitations of the prevailing approach to communicative competence; Part III describes a conceptual re-framing of language use as ecological languaging in terms of embodied, situation-sensitive action through which people coordinate with others, artefacts, and environments; Part IV explores assessment approaches built on Bayesian principles for tracking learner development and progress by taking account of prior accomplishment, expert opinion, and emerging performance to create probabilistic trajectories; Part V focusses on professional developments related to conceptual refinement, curriculum design, teaching materials, and teacher education. Part VI considers some key future challenges. This title is also available as Open Access on Cambridge Core.