This paper advances conceptual tentative bases for understanding workplace pedagogic practices. It proposes that whether arising through everyday work activities or guided learning in workplaces, learning is shaped by workplace participatory practices. This learning is held to be co-participative: the reciprocal process of how the workplace affords participation and therefore learning, and how individuals elect to engage with the work practice (Billett 2001b). In order to make a space to understand workplaces as learning environments it is necessary for them to be discussed and conceptualised on their own terms. Describing learning through work as 'informal' is negative, imprecise and denies key premises about participation in and learning through work. Access to workplace activities and guidance, and the distribution of opportunities to participate are structured by workplace factors. Much of this structuring has intentionality associated with the continuity of the work practice through participants' learning. Workplace experiences (activities and interactions) are, therefore, not 'adhoc' or 'informal', they are a product of the historical, cultural and situational factors that constitute the work practices and its enactment, and individuals' engagement in those practices. These factors shape the activities, goals and interactions afforded by the work practice and how individuals construe and learn through them Learning is conceptualised as arising inter-psychologically through participation in social practices such as workplaces. It is not reserved exclusively for or peculiar to particular experiences. However, particular kinds of experiences (e.g. routine or non-routine activities) are likely to have particular learning kinds of learning consequences. However, learning through participation needs to be considered critically. Although intersubjectivity (shared understanding) is seen as an important goal in the development of vocational practice, it offers a limited conception of goals for learning, as it is largely reproductive. The appropriation of individuals' knowledge through workplace practices needs to be seen in terms of its worth and adaptability, not just its salience at time and place of learning. Therefore, in considering the kinds of processes adopted and outcomes arising from participatory practices in workplaces a critical stance is warranted.