This paper is concerned with two related methodological problems. First, presented with a complex social scenario of a meeting between the representatives of different social welfare agencies, how should we make sense of this meeting? Second, in the context of the potential insights that the complexity sciences offer for understanding the social world, how can we translate those models to make sense of complex social dynamics? The example of the meeting, taken from an ethnographic study of collaboration in social welfare, is used to situate debates about the use of complexity science in knowing the social world. Drawing upon the work of Luhmann, I argue that we need to re-think the insights complexity sciences in order to situate the problem of complexity in the social world itself. Doing so locates the problem of knowing the social world in the social world itself, and highlights the necessary role of ignorance both in social life itself, and in knowing the social world.