Graduate students and novice researchers face various challenges in their study programs or workplaces, including a research-focused curriculum and high research expectations at the expense of other areas of responsibility that would allow for training and socializing in their environment. The involvement in participatory action research (PAR) is a lever for supporting the professionalization of apprentice and novice researchers by promoting their training through the development of skills adapted to individual circumstances and by fostering their socialization in the academic environment. The results of the analysis of 63 reflective logbooks, two focus groups, and 20 individual interviews show professionalization in both areas of training and socializing. More specifically, the four professional skills that were most developed are project management, collaboration, digital, media, and information literacy, and communication. In terms of socialization, the experience of performing research differently, the implementation of horizontal governance, the varied distribution of responsibilities among participants, the work in multidisciplinary teams, and the hands-on learning of the PAR process played a decisive role. A discussion follows on the potential of PAR for the professionalization of emerging scholars, focusing on the strengths and distinctive features of their experience.