This edited volume is a collection of articles focusing on the role of agency in the activity of translators and interpreters. Situated within the sociology of translation, this volume employs a number of approaches from the social sciences. The articles illuminate the concept of agency from various methodological perspectives: activity theory, agency theory, network analysis, and explaining by social mechanisms are brought into a fruitful discussion with Translation Studies. The analysis of the agents is deeply embedded in the surrounding practices and professional environments of the translators and interpreters in question. With the help of both historical and contemporary data, the writers investigate agency in the fields of literary translation, court interpreting, and subcontracting translators, and in contrast to the neighbouring professional field of technical communication. These articles, therefore, reveal the complex and situated nature of the social practices of translating and interpreting.