Decades of research on workplace learning has reinforced that professionals learn through work; however, organisational learning practices have often not shifted to recognise or facilitate this learning. This article presents findings from an interview-based study of professionals in Australia that investigated their experiences of work and learning in a variety of complex adaptive organisations. The focus of this article is on a particular aspect of the study's findings which identified that, despite the organisations studied espousing support for learning through work, the professionals interviewed described learning through engaging in 'fluid work', and that organisational learning and development systems and practices were still largely oriented towards formality and structure. The study contributes to the research field of work and learning, through the use of complex adaptive systems theory to examine how organisational complexity influences professionals' experiences of work and learning. It also empirically indicates the interrelatedness of work and learning in complex adaptive organisations. The implications of this study suggest that the focus for understanding and reforming organisational learning and development systems and practices needs to shift away from structure and measurement and towards the interplay of organisational complexity, fluidity of work, and experiences of learning primarily through work.