This chapter explores the connections that may exist between research methods based on ethnographic observation and training programs addressed to practitioners. In the filed of applied linguistics, a growing body of research has recently investigated the conditions in which workers use language in the context of their professional practice. However, few of these research have explained how their findings can inform practice and how training activities can assist transfer between scientific knowledge and professional competences. Based on a research experience of almost ten years in the field of apprenticeship training in Switzerland, the chapter explains how the research outcomes associated with a direct observation of naturally occurring training practices in the workplace can provide a useful material for training vocational trainers and workplace supervisors.