Sociocultural constructivist perspectives advance learning in and through work as the process and product of workers' situated participation in practice. Such participation is invariably interactive and personally enacted in the many ways workers' engage in the activities and events that characterise their practice. Further, the nature of engagement in work practice is transformation: nothing is static, nothing remains the same. At its simplest, workers are always in the constant transformational state of doing something. The something they are doing is most often visible in some form or other as occupational practice that is historically founded, collectively defined and socially produced albeit through the personal and often idiosyncratic enactment of that practice. This chapter focuses on the transformational nature of work and its description and explanation as learning. Drawing on concepts of agency and Dewey's ideas of transaction, the chapter explores and discusses ways of making the transformational qualities of workers' personal work practices more visible as a means of understanding how change is enacted as learning through work and what changes are emergent as evidence of workers' learning. These discussions draw on data and findings from a research project that examined workers' personal work practices. The research focused on workers' self-description and explanation of the particular ways they went about their work, the purposes and outcomes accomplished through their personal practice and the kinds of personal and situational changes they accounted as evidence of their learning. From the findings of that research, the chapter elaborates three kinds of sets of transactions. They are (1) transacting identity through forms of social engagement, (2) transacting goals as personal aspirations and shared purposes and (3) transacting the material as tools and procedures. These sets of transactions are advanced as possibilities for overcoming the limitations of interaction as the primary concept used to define the activities that underpin describing and explaining work-learning as participative practice. Data samples from the interview transcripts of one of the three firefighters who participated in the research are used to illustrate the complex integration of personal and contextual factors that accomplish the transformations of person, place and practice that are the evidence of learning in and through work.