The aim of the present study is to contribute to the analysis of employment and work conditions of Portuguese trainers, as well as to identify conditions, resources, demands and constraints of their work activities. Despite the lack of scientific knowledge on professional training, the topic has been playing a central role in modern societies. Several data collection strategies were used, namely the application of INSAT to 72 trainers, exploratory interviews with 10 trainers and collective interviews with 6 trainers. The analysis of the data collected highlights the changes in the selection of human resources in the sector as well as the contractual terms of the trainers, mainly independent workers. The intra and inter individual variability of working hours and the diversity of activities performed by each trainer also stands out. Finally, it is important to refer the spontaneous organization of trainers' work activities according to their training modality.