Individuals' dispositions have long been held to direct and energise cognition in ways that shape how they experience and respond to events in the social world. Therefore, a consideration of these dispositions is likely to be helpful in understanding the inter-psychological processes between individual and social world that frame contemporary socio-cultural accounts of learning. Here, the specific concern is to elaborate the sources, legacies and potency of individuals' dispositions in the learning of occupational practice through these processes. Having reviewed ideas about the dispositional underpinnings of individuals' construal and construction of the knowledge required for work, these conceptions are exercised through illuminating the roles dispositions play in the process of constructing the knowledge required for an occupational practice (i.e. hairdressing). The study reported here combines workplace ethnography and problem-solving tasks to identify the source of these subjectivities, how they shape individuals' cognitive processes at work tasks and their learning through participation in vocational practice. In all, it identified how individuals' dispositions arise through socially-shaped life histories or ontogenies, albeit in person-dependent ways. The participants' conceptions, preferences and procedures that shape their learning and the enactment of their practice were found to be products of earlier socially-derived experiences, thereby making them personally-subjective. These personally-subjective dispositions were identified as shaping how these individuals engage in work, learning and the ongoing remaking of work activities, because they influence inter-psychological processes that comprise the immediate experiences that constitute the enactment of these activities. So, this suggests that the sociogeneses of knowledge and learning likely includes personally unique social contributions that arise through ontogeny.