This paper explores the impact of video on situated dialogic action research. The paper discusses collaborative encounters with a manager who was given a small video camera. The manager had been tasked with making a new market and was asked to "show me how you make a market". The paper discusses how the emergent ‘knowing-practising’ of the new market was constructed through the dialogical relationship between a practitioner, a researcher and a videotape. The findings describe how a managers and a researcher reflect, talk and make sense of practices and markets, developing theories to help the manager work out what the new market might be and how he might shape it in ways that gives his firm a active place in that market. Video offers a way to capture and explore the transformations of market representations and the work managers do at the level of situated practice as they work out theories of action.