This chapter explores how a mapping of knowledge and ignorance mobilization dynamics in science can play a role in science evaluation and policymaking. The standard science epistemic map – where only knowledge is valued – is thus unfolded, making knowledge and ignorance mobilization dynamics more visible. An emphasis on mapping is in keeping with practices by natural scientists who construct visualizations for natural scientific knowledge, making it more visible and thereby hopefully easier to communicate. The use of mapping is enlisted to make scientific knowledge and ignorance dynamics. Nescience is understood as the complete absence of knowledge and therefore lies outside of the mapping. Multiple actors including scientists, policymakers, stakeholders, brokers, and funders can engage in knowledge and ignorance mobilization. Moreover, a focus on epistemic dynamics might wrongly convey simplicity in post-market surveillance. Simplicity belies underlying complexity. Active non-knowledge was explicitly acknowledged in science evaluation.