The analysis of naturally-occurring spoken interaction is an area which has attracted growing interest over the last few years. In this issue, Paul Seedhouse reviews Conversation Analysis (CA) and its application to areas of language learning and teaching, including teaching languages for specific purposes, materials design, classroom interaction and proficiency assessment. The author then examines the complex issue of what CA can contribute to the study of ‘learning’ and discusses the contribution of CA as a tool in existing social sciences research methodologies.