Translation is a critical issue in international mathematics education studies but has seldom been carefully investigated. How can a theoretical approach be translated and subsequently used in different languages, and to what extent could the translation processes deepen the approach itself? This paper addresses such issues in the case of the Documentational Approach to Didactics (DAD). We explore possibilities of translating selected critical notions expressed in English terms into French, Arabic, and Chinese, and of developing insights from these. We further deal with the translation issues 'in situ', i.e., in an English mathematics teacher's lesson where we can identify the embodiments of the DAD concepts. The most challenging part in the translation is the embedding of the English terms in the English cultural sphere, and 're-bedding' them into another cultural sphere. It is claimed that examining the nuances between the different possibilities of translation for the same concept in connection with their use 'in situ', and drawing inspiration from the educational, cultural, and theoretical traditions in other cultural spheres, can help to deepen the theoretical constructs.