New forms of work practice emerge as workplaces are transformed by changes in technology, global competition and employment practices. Consequently, learning for work becomes an ongoing project throughout individuals' working lives as they seek to maintain and further develop their work practice. This chapter examines learning as participation in work from an activity theory perspective. It proposes that work practice, the requirements for performance at work and the learning of those requirements, are both constituted in and distributed across the circumstances where the work is enacted --- the workplace. Therefore, understanding how individuals learn at and through work necessitates accounting for how workplaces afford individuals opportunities to develop the capabilities to address these requirements. Moreover, as workplaces are contested rather than benign environments, these affordances are likely to be distributed asymmetrically across the work force.