Trainee teachers in Further Education (FE) come from disparate social and professional backgrounds. These disparate backgrounds can influence how they conceptualise themselves as teachers, often resulting in significant cognitive and emotional disruption as they seek to adapt their previously held dispositions in light of their workplace experiences. With teacher retention rates currently low, it is important to reveal the lived experiences of FE trainees learning in the workplace so that they can be better supported to understand and manage the challenges of teaching in FE. This interpretivist inquiry builds theory by using the Bourdieusian theory of habitus as a multi-faceted concept to explore how trainees’ habituated dispositions influence their interactions with learning opportunities in the workplace, how they operationalise their capitals to develop their practical teaching skills, and the role mentors play in these processes. Data were generated using semi-structured interviews from six case studies comprising in-service trainees and their mentors. Analysis of the data shows that habituated dispositions play a significant role in trainees’ interactions with learning in the workplace, influencing their evolving teacher habitus and how they perceive and subsequently operationalise their capitals. Mentors are a key part of these processes as they support trainees to understand the culture, values and practices of the workplace field and in so doing, to become accepted and valued team members. This study adds knowledge about trainee habitus-field fit and how trainees operationalise their capitals in the field to enhance their learning. It points towards ways for mentors and teacher educators to better support FE trainees as they learn how to navigate and acculturate themselves to the education field and provides further evidence for policy-makers of the longstanding need to ensure the status of FE teachers reflects the pivotal role assigned to the sector. Finally, it identifies areas for future research, such as how FE teachers enact emotional practice and the importance of informal trainee learning.