This paper outlines a detailed and systematic method for revealing and mapping out the network mobilised in the development of a discrete innovation. This is termed a focal action-set. Important to the utility of this approach has been the development of a set of conventions for the graphical expression of the network and its components: actors, links and flows. It is argued that the network graphic provides a powerful, though under-utilised, tool for the representation of relational data. It may be employed, for example, to reveal variations in network configuration and to highlight key networking or boundary-spanning actors. The network mapping approach is illustrated through three cases of small firm innovation drawn from a wider investigation of award-winning technological innovations. A comparison between the network maps show a variation in the key boundary-spanning interactions, which is related to the organisational background of the entrepreneurial actor.